a) Jawless.

[…]the heads are inverted and agnathic (lacking a lower jaw)[…].

b) Afflicted by or characteristic of agnathia.

Mouth is without jaws (agnathic) in lampreys and hagfishes and bounded by jaws (gnathic) in all other vertebrates.

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  • agnathic — ag·nath·ic …   English syllables

  • agnathic — adjective see agnathous …   Useful english dictionary

  • agnathous — /ag neuh theuhs/, adj. Zool. 1. having no jaws. 2. belonging or pertaining to the class Agnatha. Also, agnathan, agnathic. [1875 80; see AGNATHA, OUS] * * * …   Universalium

  • agnathous — adjective /ˈæɡnəθəs/ a) Jawless. The Onchidiidæ are described as agnathous, but I am confident of having observed the jaw figured. b) Afflicted by or characteristic of agnathia. The mouth is a transverse slit, which shows no teeth, nor any jaws… …   Wiktionary

  • agnathia — Congenital absence of the lower jaw, usually accompanied by approximation of the ears. SEE ALSO: otocephaly, synotia. [G. a priv. + gnathos, jaw] * * * ag·na·thia ag nā thē ə, ( )ā nā , nath ē n the congenital complete or partial absence of one… …   Medical dictionary