1572, from M.Fr. acerbité, from L. acerbitatem (nom. acerbitas) "bitterness," from acerbus "bitter, sharp, tart" (related to acer "sharp"),from PIE *ak- "sharp" (see acrid). Earliest use in Eng. is figurative, of "sharp and bitter" persons. Acerbic in the fig. sense of "sour, harsh, severe" (of speech, manners, etc.) is from 1865.
[uh-sur-bi-tee] 
bɪ