barb

The point that stands backward in an arrow, fishhook, etc., to prevent it from being easily extracted. Hence: Anything which stands out with a sharp point obliquely or crosswise to something else.

(figuratively) A hurtful or disparaging remark.

A beard, or that which resembles it, or grows in the place of it.

(ornithology) One of the many side branches of a feather, which collectively constitute the vane.

(ichthyology) Any of various species of freshwater carp-like fish that have barbels and belong to the cyprinid family.

(US) The sciaenid fish Menticirrhus americanus, found along the Atlantic and Gulf Coasts of the United States.

(botany) A hair or bristle ending in a double hook.

(obsolete) A muffler, worn by nuns and mourners.

Paps, or little projections, of the mucous membrane, which mark the opening of the submaxillary glands under the tongue in horses and cattle. The name is mostly applied when the barbs are inflamed and swollen.

(obsolete) A bit for a horse.

A plastic fastener, shaped roughly like a capital I (with serifs), used to attach socks etc. to their packaging.