paramecium n.

before vowels, par-, word-forming element, originally in Greek-derived words, meaning "alongside, beyond; altered; contrary; irregular, abnormal," from Greek para- from para (prep.) "beside, near; issuing from; against, contrary to," from PIE *prea, from root *per- (1) "forward," hence "toward, near; against." Cognate with Old English for- "off, away." Mostly used in scientific and technical words; not usually regarded as a naturalized formative element in English.

*māk-, Proto-Indo-European root meaning "long, thin." It forms all or part of: emaciate; macro; macro-; macrobiotic; macron; meager; paramecium. It is the hypothetical source of/evidence for its existence is provided by: Greek makros "long, large," mēkos "length;" Latin macer "lean, thin;" Old Norse magr, Old English mæger "lean, thin."