A crossword theme is a set of long entries that share one consistent trick, such as a letter added, a word hidden, or a pun on a phrase. To come up with one, pick a single wordplay mechanism, list every phrase that fits it, then keep the best three to five entries whose lengths pair up symmetrically in the grid. This guide covers nine theme types, original example sets for each, a brainstorming method, and the length check that decides whether a theme can actually be built.
What makes a good crossword theme?
A good theme has four properties:
- One rule, applied consistently. Every theme entry does the same thing. If three entries add a letter and the fourth swaps one, solvers feel cheated.
- A payoff. The solver should get an "aha" when they see the trick, ideally from the first two entries, so they can use it on the rest.
- Fun, in-the-language entries. Phrases people actually say, not dictionary strings.
- Fit. The entry lengths must work with the grid's symmetry (see below). A brilliant set that cannot be placed symmetrically is a set you have to cut.
Also check that the idea is fresh. Search the public databases such as XWord Info and the Cruciverb database for your concept and your best entries before you invest in grid work. Many "obvious" themes have been done, and an editor will notice.
Which theme types can you use?
| Theme type | The trick | Typical entry shape |
|---|---|---|
| Add-a-letter | Add one letter to a phrase, creating a new, silly phrase | Phrases of 8–15 letters |
| Drop-a-letter | Remove a letter, same idea in reverse | Phrases of 8–15 letters |
| Hidden words | Each entry hides a word across its word breaks | Two- or three-word phrases |
| Puns / sound-alikes | A phrase changed by sound, clued with a question mark | Phrases of 10–15 letters |
| Before-and-after | Two phrases overlap on a shared word | 13–15 letters |
| Quote or joke | A line split across several equal-length entries | Rows of 11–15 letters |
| Revealer-based | Entries are in a category named by a final entry | 3–5 entries plus a revealer |
| Rebus | A single square holds multiple letters | Entries crossing the rebus square |
| Letter-pattern / structural | Entries share a letter pattern or construction | Varies |
Add-a-letter themes
Take a familiar phrase, add one letter to a word, and clue the new phrase as if it were real. Pick one letter and one position (here, a C at the front of the first word).
- LAW SCHOOL becomes CLAW SCHOOL, clued "Academy for crabs?" (10 letters)
- LIP READING becomes CLIP READING, clued "Studying a film trailer?" (11 letters)
- HAIR DRYER becomes CHAIR DRYER, clued "Appliance for wet furniture?" (10 letters)
Strong add-a-letter sets use the same letter in the same position every time. Some also add a revealer such as "ADD C" that names the trick, but a revealer is optional here.
Hidden-word themes
Each entry hides the same word, or words from one category, across the break between two words. Hide OWL:
- SNOW LEOPARD (hides OWL: SNOWLEOPARD)
- ELBOW LENGTH (ELBOWLENGTH)
- A third entry of your own, hiding OWL in the same way
A hidden-word theme works best when the hidden word spans the break (it starts in one word and ends in the next). If it sits entirely inside one word, it is just a word, not a trick. Clue the hidden word in a revealer like "NIGHT BIRD" or leave the discovery to the solver.
Pun and sound-alike themes
Change a phrase by sound, then clue it with a question mark. Using cheeses:
- BRIE CAREFUL (from "be careful"), 11 letters
- GOUDA RIDDANCE (from "good riddance"), 13 letters
Pun themes live and die on the groan factor and on consistency: one category (cheese, fish, birds), and every pun landing in the same way. Read each one aloud. If you have to explain it, cut it.
Before-and-after themes
Two phrases share a middle word; the answer is both phrases fused over the shared word. The clue gives both halves.
- SWEET POTATO + POTATO CHIP = SWEETPOTATOCHIP (15 letters)
- BASKET CASE + CASE STUDY = BASKETCASESTUDY (15 letters)
- BUBBLE GUM + GUM DROP = BUBBLEGUMDROP (13 letters)
These suit 13- and 15-letter slots well because the fused answers run long. The challenge is length: you need several overlaps that all land on lengths your grid can hold.
Quote and joke themes
Split a line across several entries of equal length, usually stacked in rows that read in order. This one is a good test of the length rules, because the line must break into pieces that fit symmetric slots and the breaks can fall mid-word. An invented line, split into three 11-letter entries:
- AGOODCLUEIS
- ASMALLDOORL
- EFTUNLOCKED
("A good clue is a small door left unlocked"). Three 11-letter entries is 33 letters total, and 11 fits a 15-wide grid with room for blocks on both sides. Quote themes are notable for two traps: quote copyright if you use someone else's words, and clue design, because every piece needs a clue that says "part of the quote" without being boring. Write your own line, or use a line in the public domain.
Revealer-based themes
A revealer is an entry that explains the theme, usually the last theme entry. A "category" revealer works like this: the starred entries begin with card games, and the revealer is DEALER'S CHOICE.
- POKER FACE (9)
- BRIDGE LOAN (10)
- WAR PAINT (8)
- DEALERS CHOICE (13), the revealer, clued "Option at a card table, or a hint to the starred answers' first words"
The revealer earns its place only if it sharpens the idea. If the solver understands the theme without it, you may not need one. Many strong themes have no revealer at all.
Rebus themes
A rebus square holds more than one letter (or a symbol) in a single cell. Rebus themes are a staple of Thursday-style puzzles, and the trick is that several crossing entries all need the same multi-letter square. They are demanding to build and to fill. Gridsmith's grid is single-letter, so as of this writing you cannot build a rebus theme in it. If rebus is your idea, plan the construction elsewhere or pick a different mechanism.
Letter-pattern and structural themes
Anything about the shape of the answers rather than their meaning. Examples include entries that start with doubled letters, answers that contain a run of the alphabet, or entries sharing a first-and-last letter. They are easy to explain and hard to make interesting, so they need to be tight and the entries lively.
Other families worth knowing
- Homophone themes: a variant of the pun theme where each entry swaps in a sound-alike word.
- Anagram themes: entries are anagrams of one another or of a revealer.
- Visual or grid-art themes: shapes formed by black squares or circled squares. Circles and shading are available in Gridsmith's Special Squares mode.
- Meta themes: a hidden extra answer found by solving the puzzle. Used more in contest puzzles.
How do you brainstorm a crossword theme?
- Start from something that amuses you. A phrase, a wrong word, an odd coincidence. The best seeds are the ones that made you smile.
- Name the mechanism. "Add an R," "hide a color," "change a vowel." If you cannot state the rule in one short sentence, it is not ready.
- Generate a long list. Write down every phrase that fits, not just good ones. Aim for 15 to 30 candidates. You will cut most of them.
- Sort by length. Group the candidates by letter count. You are looking for a pair of matching lengths and a center entry.
- Keep it consistent. If the strongest entries break your rule, either change the rule or drop the entries.
- Test the funniest and weakest. Cut the weakest. A theme of three great entries beats five okay ones.
- Check for prior art in a puzzle database.
Then run the length check below before you open a grid.
How do you check theme entry lengths for symmetry?
Crossword grids use 180-degree rotational symmetry: rotate the grid half a turn and the pattern of blocks is identical. Theme entries have to obey the same rule. Use this checklist:
- Entries come in mirrored pairs of equal length. An entry in row 3 needs an equal-length partner in the mirrored position, row 13 of a 15-row grid (the mirror of row r is row 16 − r).
- A lone entry sits in the center row. The center row of a 15×15 is row 8. It is its own mirror, so it can be any length that is centered or symmetrically placed.
- So: an odd number of theme entries means one in the center row, and the others pair up. Four entries must form two equal-length pairs. Five entries means two pairs plus one center entry.
- Pairs are not just any equal lengths. Two 11-letter entries pair, but the 11 and the 13 do not.
- Leave room. An entry of 15 letters fills a 15-wide row completely, so it needs no blocks in that row. An 11-letter entry needs 4 more squares in its row, as blocks or other letters.
- Spread the themers out. Avoid putting theme entries in adjacent rows. Stacked long entries squeeze the crossings and make the fill very hard.
Worked example (15×15)
Using the hidden-OWL set: SNOW LEOPARD (11) and ELBOW LENGTH (11) are an equal-length pair, so they go in mirrored rows such as row 4 and row 12. A third entry, WISE OLD BIRD (11) as the revealer, sits in the center row 8, centered at columns 3 to 13. That layout places three 11s without breaking symmetry.
| Entry | Length | Row | Mirrors |
|---|---|---|---|
| SNOW LEOPARD | 11 | 4 | ELBOW LENGTH, row 12 |
| WISE OLD BIRD (revealer) | 11 | 8 (center) | itself |
| ELBOW LENGTH | 11 | 12 | SNOW LEOPARD, row 4 |
On a 21×21 Sunday-size grid the same logic applies with the center row at row 11, and mirrored rows add to 22. There is more room for long entries, so Sunday themes often carry more themers.
In Gridsmith, symmetry is automatic: when you place a block, its 180-degree partner appears too. Use Theme mode to mark your theme entries, and the live word count and block count show whether the grid is still within your target. For the full list of grid constraints, see crossword grid rules.
What should you do after you pick a theme?
Once the lengths work, the next steps are in order:
- Place the themers and mirror the blocks (see how to make a crossword puzzle).
- Fill the grid around them, hardest areas first (crossword fill tips).
- Write clues that sell the trick (crossword clue writing).
- If you want to submit, read the NYT submission guide.
To try a theme, open the Gridsmith editor and mark your entries in Theme mode.
Frequently asked questions
How many theme entries does a crossword need?
Most themed 15×15 puzzles have three to five theme entries, and Sunday-size 21×21 puzzles often have more. The count has to work with symmetry: pairs of equal length plus at most one center entry.
Can a crossword theme have just one long entry?
Yes, if it sits in the center row and is symmetric by itself. This is common for a single long answer, such as a 15-letter entry across the middle of a 15×15.
Do I need a revealer?
No. A revealer helps when the trick is hard to see, but a clean theme often works better without one. Ask whether the solver gets the idea without it.
How do I know if my crossword theme has been done before?
Search the public puzzle databases for your concept and your strongest entries. If a very similar set already ran, rework the mechanism or change the entries. Do not copy a published theme set.