In William Shakespeare's Othello, the use of imagery and metaphors is significant in conveying meaning as it helps to establish the dramatic atmosphere of the play and reinforce the main themes. Through this, the audience is able to grasp a better understanding of the play. .
Throughout Othello, images relating to poison frequently occur. These references are predominantly made by Iago. This seems appropriate for Iago who exhibits the characteristics of poison; they being fatal and deadly. There are several possible explanations to what motivates Iago: being overlooked for the lieutenancy, the belief that Othello and Cassio had committed adultery with his wife, though this is never really proved; class differences present in the society that made him feel inferior, and racial differences. This desire for revenge is so great it "doth, like a poisonous mineral, gnaw [his] inwards." Iago's use of language is a primary weapon in manipulating Othello. By "pour[ing] this pestilence into his ear", Iago contaminates his thoughts. Once Othello starts to doubt Desdemona's fidelity, he is so incredibly driven by jealousy that it leads him to murder her, ironically with poison. .
Many references are made to animals in the play. Iago uses beast imagery to express his contempt and to downgrade those he despises. Early in Act 1, he rouses Brabantio's anger by using crude images of animals fornicating to inform him that his "daughter and the Moor are now making the beast with two backs." Such a metaphor is designed to evoke a strong emotional response. In a soliloquy at the conclusion of Act One, Iago says "It is engendered. Hell and night / Must bring this monstrous birth to the world's light." Shakespeare uses the image of a monster being born as a metaphor for the start of Iago's evil scheming. It also becomes evident that Othello's mind has been corrupted by Iago's evil handiwork when he too starts to use the same sort of animal imagery in his speech.