1. Literally, to growl at one in a vicious manner and with teeth bared. I knew not to approach the dog when it started snarling at me. The poor woman was so overcome by delirium that she actually snarled at the doctors and nurses.

2. To speak or respond to one in a particularly nasty or aggressive manner. She positively snarled at me when I suggested that she should take a break to focus on her kids. If you snarl at me like that again, I'm sending you straight to bed.

3. To utter something at one in a particularly nasty or aggressive manner. In this usage, a noun or pronoun is used between "snarl" and "at." He snarled his answer at me, so I knew not to push him any further. I got so sick of the coach snarling orders at us, so I quit the team.