n.
Pronunciation: ' s ī n-y ə - ˌ so ̇ id, ' s ī -n ə -
Function: noun
Etymology: Medieval Latin sinus sine
Date: 1823
1 : SINE CURVE , SINE WAVE
2 [New Latin sinus ] : a minute endothelium-lined space or passage for blood in the tissues of an organ (as the liver)