What is "amphid"

Amphid \Am"phid\, n. [Gr. 'a`mfw both: cf. F. amphide.] (Chem.) A salt of the class formed by the combination of an acid and a base, or by the union of two oxides, two sulphides, selenides, or tellurides, as distinguished from a haloid compound. [R.]
--Berzelius.

n. (context nematology English) One of a pair of chemosensory sense organs positioned laterally on the head of a nematode

Amphids ( Greek: amphi, around, double) are innervated invaginations of cuticle in nematodes. They are usually found in the anterior (head) region of the animal, at the base of the lips. Amphids are the principal olfactosensory organs of nematodes. Each amphid is made up of 12 sensory neurons with ciliated dendrites.