词根词缀：-oid, -oidal, -oidism, -odic

【来源及含义】Greek: a suffix; like, resembling, similar to, form

【相关词根词缀】 Inter-related cross references, directly or indirectly, involving word units dealing with "form, shape, appearance": eido-; figur-; form-; icono-; ideo-; imag-; morpho-; typo-.

【同源单词】acanthoid, acanthozooid, acaroid, acidoid, acromegaloidism, acrostichoid

词根词缀：pterido-, pterid-

【来源及含义】Greek: fern [from pter[on], "feather, wing"]

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

【同源单词】eurypterid, pteridography, pteridoid, pteridological, pteridology, pteridomania

词根词缀：ptero-, pter-, -ptera, -pteron, -pteryx, -ptery, -pterous

【来源及含义】Greek: feather; wing, winglike

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

【同源单词】Aphaniptera, apterex, apteria, apterous, apteryx, Archaeopteryx