ingredior

Ingredior, ingredi, ingressus sum: deponent, third conjugation in -ior, from in plus gradior, "to step". Passive endings throughout, active meaning throughout, so ingressus est is "he entered" and never "he was entered". The infinitive is ingredi, not ingrediri, which is the form the -ior verbs trip people on.

It takes either a plain accusative of the place entered, urbem ingredi, or in with the accusative, and there is no difference in meaning worth defending. The second sense is "to begin, embark on": ingredi iter is to start a journey, ingredi dicere is to begin to speak. The gradior family is enormous - aggredior, egredior, progredior, regredior - and English harvests ingress, egress, progress, congress and aggression from it.