Proof letters
The crossword clue "Proof letters" is answered by QED, a 3-letter entry. Used 78 times across 29 distinct years; most recently in 2025. It appears in 17 publications in the xd corpus. Every figure on this page comes from the pilot data itself.
The answer
QED
3 letters. See every clue for this answer on the QED answer page.
Used 78 times across 29 distinct years; most recently in 2025. It appears in 17 publications in the xd corpus. Frequency and last-seen figures come from the xd crossword corpus only.
Other answers for this clue
The same clue has also been answered these ways in the xd corpus. Answers inside this pilot link to their own answer page.
- QEDS (3 uses in xd)
Related clues
Pilot clues of the same answer length that share a word with this clue, or match its answer pattern when no word is shared. Most used first.
- Genetic letters - RNA, used 265 times
- Debtor's letters - IOU, used 249 times
- Explosive letters - TNT, used 225 times
- Letters before an alias - AKA, used 194 times
- Alias letters - AKA, used 146 times
- Battleship letters - USS, used 124 times
Search this clue pilot
Search by clue words or by answer, or type a pattern with the letters you have and a blank for each square you do not know. The characters _ ? . and - all work as blanks.