early 15c., via Medieval Latin, from Greek enema "injection," from enienai "to send in, inject," from en "in" (see en- (2)) + hienai "send" (cognate of Latin iacere; see jet (v.)).
enema en·e·ma (ěn'ə-mə)n. pl. en·e·mas
The injection of liquid into the rectum through the anus for cleansing, for stimulating evacuation of the bowels, or for other therapeutic or diagnostic purposes.
The fluid so injected.