A man who forces someone to give him oral sex. Comes from Catullus, the best of ancient Roman poets, who uses this word to describe a government official in poem 10.
Stay away from John; he's such an irrumator. Last time Susan slept with him, she could hardly talk the next day because her throat was so sore.
The latin word describing a man sucking another mans penis. This was considered the lowest form of sex by the Romans. A man having his penis sucked was a fellator.
Lucius Pipinna is such an irrumator.