Justus = "just"
1) a surname of Joseph, called Barsabas. Act 1:23
2) of Titus, a Christian at Corinth, with whom Paul lodged. Act 18:7
3) a surname of Jesus, a friend of Paul. Col 4:11
Part of Speech: noun proper masculine
Of Latin origin ("just"); Justus, the name of three Christians: - Justus.
Perseus Digital Library
University of Chicago's Logion lexicon
Thayer's dictionary plus other information.
From this site's dictionary (in Italian)
Click on the first column to search for that word as a form of the root Ἰοῦστος; click on the second column to search for that grammatical form of the root Ἰοῦστος; click on the third column to search for that word and grammatical form; click on the total to search for the root Ἰοῦστος.