"He's lying through ___ teeth!" (3)
I believe the answer is:
his
(Other definitions for his that I've seen before include "It belongs to him" , "Belonging to the male" , "that chap's" , "To - Coy Mistress (Marvell)" , "That man's" .)
I believe the answer is:
his
(Other definitions for his that I've seen before include "It belongs to him" , "Belonging to the male" , "that chap's" , "To - Coy Mistress (Marvell)" , "That man's" .)