From the same as klesis; invited, i.e. Appointed, or (specially), a saint -- called.
see GREEK klesis
a. "invited (by God in the proclamation of the gospel) to obtain eternal salvation in the kingdom of God through Christ" (see καλέω, 1 b. β'. (cf. Winer's Grammar, 35 (34))): Romans 8:28; 1 Corinthians 1:24; Jude 1:1; κλητοί καί ἐκλεκτοί καί πιστοί, Revelation 17:14; κλητοί and ἐκλεκτοί are distinguished (see ἐκλεκτός, 1 a.) in Matthew 20:16 (T WH omit; Tr brackets the clause); Matthew 22:14, a distinction which does not agree with Paul's view (see καλέω, as above; (Weiss, Biblical Theol. § 88; Lightfoot's Commentary on Colossians 3:12)); κλητοί Ἰησοῦ Χριστοῦ, genitive of possessor (Winers Grammar, 195 (183); Buttmann, § 132, 23), devoted to Christ and united to him, Romans 1:6; κλητοί ἅγιοι, "holy (or 'saints') by the calling of God," Romans 1:7; 1 Corinthians 1:2.
b. called to (the discharge of) some office: κλητός ἀπόστολος, i. e. divinely selected and appointed (see καλέω, as above), Romans 1:1; 1 Corinthians 1:1 (L brackets κλητός); cf. Galatians 1:15.