Source : Webster's Revised Unabridged Dictionary (1913)

Symbranchii \Sym*bran"chi*i\, n. pl. [NL., fr. Gr. sy`n with + ?
   a gill.] (Zo["o]l.)
   An order of slender eel-like fishes having the gill openings
   confluent beneath the neck. The pectoral arch is generally
   attached to the skull, and the entire margin of the upper jaw
   is formed by the premaxillary. Called also {Symbranchia}.