Home / Words / constrictNo. 0077

constrict

/kənˈstrɪkt//kənˈstrɪkt/·verb
to squeeze something from all sides so it becomes narrower or tighter
Fig. 1 — The hose is halfway through its arc over the tomatoes when my hand closes around it.
01Definition

To constrict is to squeeze from every side at once — an encircling pressure that makes the space inside smaller. Blood vessels constrict in the cold, a tight collar constricts the throat, smoke constricts the airways, and the boa constrictor wears the word as a surname: Latin constringere, 'to bind tightly together'. Where narrow only reports the loss of width, constrict names the grip that causes it — and figuratively the grip can be rules, fear or debt constricting a life.

02In use
  • iCold air makes the blood vessels in your skin constrict.
  • iiHis collar felt too tight, constricting every swallow.
  • iiiStrict licensing rules constrict the growth of small businesses.
03Collocations
  • blood vessels constrict
  • a constricted airway
  • pupils constrict
  • constrict the flow
  • constricted by rules

Family constriction (noun) · constrictive (adjective) · constrictor (noun)

04Relations

=squeeze, compress, narrow, tighten, strangle

≠dilate, expand, widen

05Compared
PairThe difference
constrict vs compressa whole mass pressed into less space, denser → compress; a channel or tube squeezed narrower around its girth, throttling what passes → constrict.
constrict vs constrainan outside limit on what something may do → constrain; a physical squeeze making something narrower → constrict.
constrict vs contractsqueezed narrower by something around it → constrict; draws itself in, smaller and tighter → contract.
constrict vs dilatethe channel is squeezed narrower and less gets through → constrict; the opening widens and more gets through → dilate.
constrict vs restrictphysically squeezed narrower around its girth → constrict; held within limits someone set → restrict.
06TOEFL & IELTS

The exam home ground is biology and medicine: vessels constrict (vasoconstriction) and dilate, pupils constrict in bright light, airways constrict in asthma — TOEFL science passages assume the constrict/dilate pair. In essays the figurative grip earns marks: regulations constrict innovation, poverty constricts choice. Keep the confusable trio straight: constrict is a physical all-round squeeze; restrict limits what is allowed; constrain forces or holds someone back.

07Asked
What is the difference between constrict, restrict and constrain?
All three tighten, in different worlds: constrict squeezes matter physically, restrict limits what is allowed, and constrain holds a maker back. Both contrasts are drawn scene by scene on the constrict vs restrict and constrain vs constrict pages in the 'Compared' list above.
What does it mean when blood vessels constrict?
Their muscular walls tighten and the channel inside narrows, so less blood flows through — the process doctors call vasoconstriction. It is how the body saves heat in the cold (surface vessels constrict, skin goes pale) and raises blood pressure under stress. The opposite is vasodilation. The verb pair constrict/dilate runs through all of physiology — vessels, pupils, airways.
Why is it called a boa constrictor?
Because constricting is its hunting method: the snake wraps its prey in coils and tightens — the same all-round squeeze the fist in the scene above puts on the hose, applied with a whole body. The name is Latin, kept whole from eighteenth-century taxonomy — boa (a large serpent) + constrictor (the binder, from constringere, 'to bind tight'). It is the rare exam word with a mascot: remember the snake and you keep the meaning.
Do pupils constrict or contract?
Standard medical usage says constrict: pupils constrict in bright light and dilate in the dark. Contract is not wrong — the iris muscle literally contracts to do it — but the eye-exam vocabulary is the constrict/dilate pair, and 'constricted pupils' (miosis) is the clinical phrase. A useful division of labour: muscles contract; the openings they control constrict.
Can constrict be used about non-physical things?
Yes — anything that grips a life or an activity from all sides: constricting rules, a constricted budget, grief that constricts the chest, small-town expectations that constrict ambition. The figurative use keeps the physical feeling of pressure closing in, which makes it stronger than restrict: a restricted diet is a list; a constricted life is being squeezed.
What is the noun form of constrict?
Constriction — both the act of squeezing and the narrowed place itself: 'a constriction in the pipe slowed the flow', 'he felt a constriction in his throat'. The agent noun is constrictor: the snake, and in anatomy any muscle that squeezes a passage shut (the pharyngeal constrictors that drive swallowing). The adjective constrictive describes whatever does the squeezing — constrictive clothing, constrictive rules.