1) Character in Othello 2) Iago was passed over for him 3) Lieutenant framed by Iago 4) Lieutenant killed by Iago 5) Lieutenant to othello 6) Othello assistant 7) Othello fellow 8) Othello murder victim 9) Othello role Found on https://www.crosswordclues.com/clue/cassio
(from the article `Othello`) The play is set in motion when Othello, a heroic black general in the service of Venice, appoints Cassio and not Iago as his chief lieutenant. ... Found on http://www.britannica.com/eb/a-z/c/33