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 collection 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 collection link to their own answer page.
- QEDS (3 uses in xd)
Other clues for QED
Every other clue in this collection answered by QED, most used first.
- Proof-ending letters - used 25 times, most recently in 2024
- Proof abbr. - used 22 times, most recently in 2015
Related clues
Clues in this collection 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
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