Word Wheel

Nine letters, one at the hub. Find every word of four or more letters that uses the centre — and the one word that uses all nine.

What it is

A ring of eight letters around a central ninth. Each answer must use the centre letter and only letters shown on the wheel, no more times than they appear. The target — how many words there are to find — is printed, and there is always one word using all nine letters.

How to play

Fix the centre letter in mind; every word contains it. Work up by length: four-letter words first, then five, hunting for the hidden nine. The printed count tells you when you have them all.

Purpose

The British newspaper staple (the Nine Letter Word or Word Wheel) that the catalogue lacked, and one whose guarantee is unusually strong: the answer key is the complete list of valid dictionary words, found by an exhaustive scan, so the printed target is provably exact — not an estimate a setter hoped was right.

History

Word wheels spread through The Guardian, The Times and The Washington Post through the 1990s and 2000s, and multiplied on mobile puzzle apps. The form descends from the older “how many words” letter games.

This implementation

• Spec knobs: letters (nine, centre first; empty picks a nine-letter word per seed), difficulty, cell.
• Generation: the nine letters come from a real nine-letter word, so a full-nine answer always exists; the ring is shuffled per seed. The dictionary is a vendored list of ~1,700 common four- to eight-letter words (kept in the crate, so it leans on no other generator), scanned exhaustively for every word spellable from the wheel through its centre.
• Guarantees: deterministic per seed; the answer key is the complete valid set (checked by an independent re-scan in the tests); a nine-letter answer always present. Rated by how many words there are to find — more is easier — with the basis named in the metadata.