Sometimes it's difficult to hold your tongue. Maybe someone is making snarky comments, saying things that are blatantly wrong, or outright attacking you verbally. The human response is to retaliate, right the wrong bring done, shut down the other person.
What I have found though, when dealing with others whose tongues are loose and words fly before being considered, even a calm and objective response will usually heighten a situation. Despite offering a calm headed, reasonable response, the antagonizer is only pushed farther into their ignorance.
So, I stay silent. Be it a mild offensive or something more, my response (as much as possible) is to remain silent. Remaining silent is beneficial in other circumstances as well. The company meeting, a sales pitch, when meeting someone new, always try to listen more than you speak. As the saying goes, our ratio of ears to mouth is 2:1 after all.