I had never heard of this term.
From Ohio DOT "Bridge term definitions":
Bent
Part of a bridge substructure. A rigid frame commonly made of reinforced concrete or steel that supports a vertical load and is placed transerse to the length of a structure. Bents are commonly used to support beams and girders. An end bent is the supporting frame forming part of an abutment.
Each vertical member of a bent may be called a column, pier or pile. The horizontal member resting on top of the columns is a bent cap. The columns stand on top of some type of foundation or footer that is usually hidden below grade.
A bent commonly has at least two or more vertical supports. Another term used to describe a bent is capped pile pier. A support having a single column with bent cap is sometimes called a "hammerhead" pier.
I assume a "crutch bent" is placed next to a failing bent to shore it up.
Today is national 'Learn Something New About Bridges Day'!