Hastings' Dictionary of the New Testament 
Clopas ( Κλωπᾶς).—Mentioned in John 19:25 as a relative, probably the husband, of one of the women who stood by the cross (Μαρία ἠ τοῦ Κλωπᾶ). By Chrysostom he was identified with Alphaeus; but this is improbable (See Alphaeus). For his connexion with Joseph and the family of Jesus, see art. Brethren of the Lord and Hasting's Dictionary of the Bible, vol. i. p. 322. According to certain apocryphal Acts of the Apostles, he is the same as the Cleopas of Luke 24:18. In that case the devotion which kept Mary of Clopas near the cross till the end finds a counterpart in her husband’s sorrow at the Crucifixion. But the identification rests on the derivation of both names from a common Greek original, Cleopatros, and is denied by those who regard Clopas as a Semitic name (see Deissmann, Bible Studies , English translation p. 315, n. [Note: note.] 2).
C. T. Dimont.
Hastings' Dictionary of the Bible 
CLOPAS (AV [Note: Authorized Version.] Cleophas ) is named only in John 19:25 . See AlphÃ¦us and Brethren of the Lord.
Holman Bible Dictionary