词根词缀：proto-, prot-

【来源及含义】Greek: first; foremost, front, earliest form of, original, primitive; chief, principal; usually used as a prefix

【同源单词】apolipoprotein, cryoprotein, fetoprotein, glycoprotein, hyperlipoproteinemia, hypolipoproteinemia

词根词缀：ptilo-, ptil-, ptilono-

【来源及含义】Greek: feather [soft], down

【相关词根词缀】 Related "feather, feather-like; soft down, plumage" word units: penna-; pinni-, pin-; plum-, -plume; pterido-; ptero-.

【同源单词】cryptoptile, haploptile, mesoptile, metaptile, neossoptile, protoptile