Webster's Revised Unabridged Dictionary · 1913

Faucal

Faucal , adjective

[Latin fauces throat.]

(Phonetics) Pertaining to the fauces, or opening of the throat; faucial;
(Phonetics) produced in the fauces, as certain deep guttural sounds found in the Semitic and some other languages.
Ayin is the most difficult of the faucals. — I. Taylor (The Alphabet)