I. adjective
1. : driven together (as the broken ends of a fractured bone)
2.
a. : wedged into a passage (as a fetus in the birth canal, a calculus in a duct, a foreign body in the larynx)
b. of a tooth : wedged between the jawbone and another tooth
impacted and unerupted normal teeth are excised — K.H.Thoma
I. adjective
: deeply entrenched : not easily changed or removed
the impacted cynicism about most things American — W.F.Buckley b 1925