Breath or helium, On a string in a child's hand. Or airbourne basket.

I swell with air, a rubbery moon, Pricked just right, I let out a tune, What am I, that might pop soon?

It’s named for the action used, towards you, it opens. Take away the last two: Standoff, sketch, or bring closer. One of junk, one of tools, one of payments at grocers. Less the first: sounds like a growl, when ‘effeminate’s certain.

A persona to maintain online anonymity. A facial accessory at a fancy dance. Encryption to obscure the key. Or a green-skinned curse if you take that chance.

What do you put on a bagel, to make sure nobody steals it?