The two men knew each other vaguely, but could not be called friends, let alone blood brothers.
Usually there's at least somebody you know vaguely, but not there, no.
The other man he vaguely knew as one of Vandoorm's men.
She was, he knew vaguely as a child knows, soon to give them all a little sister.
I knew vaguely that her nephew had been in trouble but wasn't sure just what he'd done.
She was the sister of some seaman he vaguely knew.
I heard voices, and knew vaguely that they weren't us.
The house was packed full of people I knew vaguely.
I vaguely know the face, but can't put a name to him.
"I only knew vaguely what a switching power supply was."