Get ready to bite (6)
I believe the answer is:
teethe
'get ready to bite' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for teethe that I've seen before include "to suffer in infancy" , "Of baby, grow molars, canines etc" , "experience eruption, by gum!" , "Cut one's dental fixtures" , "Develop gnashers" .)