What are some examples of violence against women in Othello?

Obviously, the entire narrative of Othello builds toward a horrific act of misogynistic violence: Othello's murder of Desdemona in the play's final scene. This crime is presaged by the painful moment in Act IV, Scene 1 when Othello strikes Desdemona ("I have not deserved this," she responds), and echoed near the play's conclusion in Iago's own murder of Emilia.

But beyond these three instances of physical violence against women, I think your question is best served by considering the pervasive varieties of verbal, social, and emotional harm inflicted against women in the deeply patriarchal world of the play. Emilia (who, being married to the profoundly misogynistic Iago, is something of an expert on the ways in which men subdue and marginalize women in both public and private life), advises the newlywed Desdemona with this pungent analogy: "'Tis not a year or two shows us a man. / They are all but stomachs, and we all but food. / They eat us hungerly, and when they are full / They belch us." In Emilia's painful experience, the salient quality of men is their rapacious swiftness to possess, use, and drain women—sexually, socially, economically, emotionally—before discarding them. And although this extremely dark view of male-female relations is derived from her relationship with a man who embodies the worst and most self-serving aspects of patriarchal ideology, non-physical forms of violence against women are rampant in Othello. We see this first in Brabantio's possessiveness toward his daughter Desdemona, and then, more catastrophically, in Othello and Iago's escalating cruelties toward their wives.

It's important to remember that Othello and Iago are both military men, and that the military culture in which the play is set is both emphatically masculine and founded on violence. Othello, Iago, and even Cassio with his callous and belittling attitude toward Bianca, are men infected to their bones by the norms of a culture in which the the marginalization and domination of women are deeply ingrained patterns. Dehumanizing language toward women courses through the play—and through the minds of these characters—like poison. And Shakespeare shows us how such a proliferation of ideological violence leads inexorably to physical violence.

The insight of Iago is the psychological fragility of any man whose sense of himself is contingent on the empty, socially-constructed ideal of his wife's chastity, and the ease with which such sexual possessiveness can be converted into physical violence. The insight of Othello, the play—an insight which so far transcends the social and political context in which the play was written that our own society continuously fails, 400 years later, to catch up to it—is that any ideological system which regulates, commodifies, and/or demonizes the sexuality of women to preserve the cultural dominance of men is itself violence.