ent-
Prefix
Meaning
A prefix signifying within. See Ento-.
Source: Webster's dictionaryExamples
In some cases, the prefix particle ent- (negation) can be considered the opposite of particle be-, while er- can be considered the opposite of ver-.
On the other hand, verbal prefixes are still much in use: be-, er-, ent-, ge-, ver-, zer-, and miß-.