词根词缀：a-, an-

【来源及含义】Greek: prefix; no, absence of, without, lack of; not

【相关描述】These prefixes are normally used with elements of Greek origin, a- is used before consonants and an- is used before vowels.

It affects the meanings of hundreds of words.

There are too many words that use these prefix elements to list all of them on this site; however, there are significant examples listed in this and the other units where they exist.

【同源单词】abacterial, abaptism, abarognosis, abasia, abiocoen, abiogenesis

词根词缀：-ous, -ious, -eous

【来源及含义】Latin: full of or having the qualities of; in chemistry, a suffix denoting that the element indicated by the name bearing it, has a valence lower than that denoted by the termination -ic; as, nitrous, sulphurous, etc., as contrasted with nitric, sulphuric, etc.

【相关描述】Only a small number of the hundreds of examples are presented because there are just too many to include at this time.

【同源单词】abdominous, abiogenous, ablepharous, abstemious, acanthaceous, acanthocephalous

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