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：gnatho-, gnath-, -gnatha, -gnathan, -gnath, -gnathia, -gnathic, -gnathous

【来源及含义】Greek: jaw

【相关描述】The jaw is the name applied to the bones which contain the teeth.

The two upper jaw-bones, the maxillae, are firmly attached to the other bones of the face.

The lower jaw, the mandible, is shaped in a form similar to that of a horseshoe, and, after the first year of life, it consists of a single bone.

It forms a hinge-joint with the squamous part (thin, plate-like section) of the temporal bone, immediately in front of the ear.

Both the upper and the lower jaw-bones include deep sockets known as alveoli, which contain the roots of the teeth.

【同源单词】agnathia, anisognathous, atelognathia, brachygnathia, chaetognath, cheilognathoschisis