What is the effect of the repeated use of the word "honest" in connection wit lago?

"Honest" emerges as a key word in this scene; it is a term laden with irony, and a constant reminder of the dramatic irony inherent in Iago's dealings. None of the characters in the play have any idea of Iago's plans and evil intentions; Othello and Cassio are especially innocent of this knowledge. Yet, the audience knows exactly what Iago is up to, and is able to see his deceptions for what they are; Iago's words interest the audience because of how much dramatic irony they are laden with, and curiosity to find out whether Cassio and Othello will come to know as much as the audience does about Iago's deviance. The word "honest" draws attention to how Iago's machinations are hidden from the characters onstage, and shows how he promotes an incorrect impression of himself in order to gain power over people.