en-, em-, el- (Greek: in, into, inward; within; used as a prefix).The en- changes to em- before b, p, or ph.embolism: 
embryo: 
empathy: 
emphasis: 
emphysema: 
emporium: 
encephalitis: 
encircle: 
encyclical: 
encyclopedia: 
enemy: 
energy: 
engrave: 
enopscilium: 
enopsilosis: 
enpodonyx: 
enthusiasm: 
enzootic: 
enzyme: 
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