noun

constraint

kuhn-STRAYNT/kənˈstreɪnt/

A limit on what can happen or be done.

The short tether is a constraint that keeps the dog from reaching the ball.

A short tether prevents a dog from reaching a distant ball, clear physical limit, dog comfortable.
Etymology

Binding tightly together provides the underlying image: a constraint holds action in check as a bond holds a body. The historical senses of binding and compulsion connect this image to an abstract restriction.

In context

Airbus Cockpit Coach2:49
enter FL180 as an altitude constraint, and press INSERT. Now we have a FL180 restriction at the abeam TOID point.
A320 ABEAM PTS Explained (MCDU DIR TO) — What It Does & When to Use It

More examples

  • Time constraints prevent us from visiting every museum.
  • The team designs a new playground within strict budget constraints.
  • Reliable transportation removes a major constraint on where she can work.

Forms

constraint · constraints

constrain verb — To limit what someone or something can do.

Similar words

restriction
Often suggests an imposed rule rather than a practical obstacle.
limitation
Can emphasize limited ability or capacity rather than external conditions.