(informal) A difficult problem or puzzle.

(medicine) An irreversible loss of brain function and cessation of brain activity.

(medicine, not comparable) Having an irreversible loss of brain function and cessation of brain activity. / (colloquial) Having no useful thoughts; stupid; ditzy.

The collective replacement parts used to repair an automobile's worn down brakes.

(idiomatic) To beat someone very severely.

A form of brake, used on bicycles, in which a pair of arms, carrying brake pads, move inwards and press on the rim of the wheel.

(marketing, Internet) A company's online brand personality, which is a summary of what users are saying online about the organization and its brands.

A tee pipe fitting with female connections on the two straight ends and a male connection on the branch.

(informal) The temporary inability to think properly, or to remember something

The characteristic of being brainy.