I am in the process of translating Sister Sledge's "B.Y.O.B" song into Russian. Could you please help me to grasp the meaning of the "Man of the room" idiom used in this song?
"Man of the" is used to describe the most important man or the man in control of whatever the object is. "Man of the house" is the most common phrase; "man of the room" would be a variant. It describes someone who is probably known by most of the people in the room or is the one person who could be labeled as the most powerful; richest; etc. Without more context from the song it will be hard to pin down the precise meaning.
Other uses you may hear (with mixed acceptance):
"Man" is, of course, just one word that could be used:
The phrase is extremely flexible.
I listened to the song here. I think the line you are referring to is "You've been hitting on every man in the room." at 00:20. In other words, the woman the song is addressed to has shown up at a B.Y.O.B. (bring your own baby) party without a date and is trying to steal someone else's man.