Also see definition of "Lucas" in Word Study
luminous; white ( --> same as Lucius)
Lucas [ebd]
a friend and companion of Paul during his imprisonment at Rome; Luke (q.v.), the beloved physician (Philemon 1:24; Col. 4:14).
LUCAS [isbe]
LUCAS - lu'-kas, loo'-kas. In Philem 1:24 the King James Version, for "Luke" (Revised Version).
Also see definition of "Lucas" in Word Study