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Updated June 2026
a cavity within a bone, especially in the skull
“The blocked sinus caused a persistent headache.”
si·nus
"Sinus" repeats a letter (4 unique of 5), so it rules out fewer options as an opening guess. Its 2 vowels balance the consonants.
"Sinus" is worth 5 points before board bonuses. Aim its letters at double/triple-letter and word squares to lift the score.
Look up sinus in an authoritative dictionary for full definitions, pronunciation, and etymology.
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