What is "sussing"

Usage examples of "sussing".

I had a lovely time wandering the shops, noshing a bit, sussing out antiques.

He owns most of the Old Bill on the Island, and I want to spring an old mate without Lewis sussing anything about it.

Anyway, we spent a couple of months schlepping round these country houses, sussing out what was where, what was worth nicking and what the security was like.

Fortunately us fellows have got a talent for sussing out lies, or ought to have.