'Trilingual' definitions:

Definition of 'trilingual'

(from WordNet)
adjective
Using or knowing three languages; "trilingual speakers"

Definition of 'Trilingual'

From: GCIDE
  • Trilingual \Tri*lin"gual\, a. [L. trilinguis; tri- (see Tri-) + lingua tongue, language. See Lingual.] Containing, or consisting of, three languages; expressed in three languages. [1913 Webster]
  • The much-noted Rosetta stone . . . bears upon its surface a trilingual inscription. --I. Taylor. [1913 Webster]