Can you give a clue that is a word on the board in Codenames?
No. While a card is still uncovered, you can't say any form of its word, or any part of it if it's a compound word. Once that card is covered, its word is fair game again.
The rule:
In Codenames, you can’t give a clue that is any form of a word still uncovered on the board, or any part of an uncovered compound word. Once that card is covered, its word is fair game again.
Not allowed while the card is uncovered:
- any form of the word: plurals, tenses and other endings (painted or painter while PAINT is showing)
- any part of a compound word on the table (sun or flower while SUNFLOWER is showing)
Allowed:
- any of those words once the card has been covered
- a word that only contains the same letters by coincidence; the rulebook warns against being too strict here
- a word that used to be a compound long ago but isn’t thought of as one today
If you’re unsure, ask the opposing spymaster quietly. If they allow it, the clue is valid.
Example:
WATERFALL is still uncovered, so the spymaster can't say water, fall or falling. Two turns later WATERFALL has been covered, and water: 2 is now a legal clue.
Why players argue about it:
Groups disagree on how strict to be. The rulebook asks for common sense: a clue that only happens to contain the same letters is fine. When a spymaster isn't sure, they check quietly with the other spymaster.