Foal (fōl), n. [OE. fole, AS. fola; akin to OHG. folo, G. fohlen, Goth. fula, Icel. foli, Sw. fåle, Gr. πω̑λοσ, L. pullus a young animal. Cf. Filly, Poultry, Pullet.] (Zoö.) The young of any animal of the Horse family (Equidæ); a colt; a filly.
Foal teeth(Zoöl.), the first set of teeth of a horse. — In foal, With foal, being with young; pregnant; — said of a mare or she ass.