It is just to edgy or rounded to answer

Not minding your own business. Oh, in construction- rounded edges- bullnose....

Who knows?  

Looks like Barbara Todaro did.

Actually, so did I but she was here first.  

That is when tenants spy on each other.

that's an easy one....the rounded edge of a tread (step)

It's what Tucan Sam does!

Projection beyond the riser

I like Barbara Todaro's answer.

Rounded edge or that thing that kids and dogs do to windows to make nose prints.

None ya damn business varmint! ;)

Tony and Suzanne Marriott, Associate Brokers - are you talking about the neighbors? lol.

When two boards meet in a corner, sometimes one side sticks out beyond the right-angle corner.  That's the 'nosing'.  On a stair, it's always the horizontal board that has nosing.  On a flat roof, the nosing is vertical, and keeps the pebbles in (although they may call it by some other name on a roof).

what my poodle does when he meets someone new? 

Ask any 70+ lady who works a citizens watch

Nosing is a term used in trimwork indicationg a rounded edging piece.

Don't be nosing around in my business. LOL!!

Has to do with steps

Sorta like snooping

Is it like nosing around the construction site?

I'm going with my Paesana Barbara Todaro 

I do not know.

Rounding off sharp corners.

Horizontal projection of an edge from a vertical surface.  Terminology used primarily in stairs.

I think of nosing as the different edges on countertops.

Bull, or cow?

Tony and Suzanne Marriott, Associate Brokers Barbara Todaro has this one.