What is the meaning of Flex?

Flexibility, pliancy.

An act of flexing.

Any flexible insulated electrical wiring.

Flexible ductwork, typically flexible plastic over a metal wire coil to shape a tube.

A point of inflection.

The act or an instance of flaunting something; something one considers impressive.

To bend something.

To repeatedly bend one of one's joints.

To move part of the body using one's muscles.

To tighten the muscles for display of size or strength.

To flaunt one's superiority.

Alternative form of flax

Alternative form of fleax

Source: wiktionary.org