En-1  prefix (also em- before b, p) forming verbs, = *in-2: 1 from nouns, meaning ‘put into or on’ (engulf; entrust; embed). 2 from nouns or adjectives, meaning ‘bring into the condition of’ (enslave); often with the suffix -en (enlighten). 3 from verbs: a in the sense ‘in, into, on’ (enfold). B as an intensifier (entangle). [french en-, latin in-]