incisive - Dictionary definition and meaning for word incisive
Incisive-> It has come from Incision cutting, esp. by a surgeon. Also , Incision sounds similar to scissor (which are your four sharp teeth) used for cutting.
incisive---incisor...cisor which is used to cut something is sharp :)
incisive sounds like insensitive >>> some one who is insensitive can kill someone with some sharp device or his words, etc