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：aesth-, esth-, aesthe-, esthe-, aesthesio-, esthesio-, aesthesia-, -esthesia, -aesthetic, -esthetic, -aesthetical, -esthetical, -aesthetically, -esthetically

【来源及含义】Greek: feeling, sensation, perception

【相关词根词缀】 Related-word units meaning feeling: senso-; pass-, pati-; patho-.

【同源单词】acanthesthesia, acatamathesia, acenesthesia, acmesthesia, acmesthetic, acouesthesia

词根词缀：photo-, phot-, -photic

【来源及含义】Greek: light; ultraviolet and infrared radiation; radiant energy

【相关词根词缀】 Etymologically related "light, shine, glow" word families: ethero-; fulg-; luco-; lumen-, lum-; luna, luni-; lustr-; phengo-; pheno-; phospho-; scinti-, scintill-; splendo-.

【同源单词】aphotesthesia, aphotic, aphototaxis, aphototropism, astrophotograph, astrophotographer