What is Snag?

Snag definition and meaning on Dictionary terms:
a tree or part of a tree held fast in the bottom of a river, lake, etc., and forming an impediment or danger to navigation.
a short, projecting stump, as of a branch broken or cut off.

any sharp or rough projection.
a jagged hole, tear, pull, or run in a fabric, as caused by catching on a sharp projection.
any obstacle or impediment.
a stump of a tooth or a projecting tooth; snaggletooth.

verb (used with object), snagged, snag