Constrict and restrict sound alike and mean different things. To constrict is to squeeze something physically narrower — an encircling grip closing on a vessel, a throat, a hose. To restrict is to limit what is allowed or how much gets through — a rule with an author: restrict access, restrict spending, restrict a diet. Constriction is the physical squeeze; restriction is the imposed limit, and often the constriction is what causes it.
Both descend from Latin stringere, 'to draw tight', but they tightened onto different objects. Constrict keeps the physical grip — com- plus stringere — squeezing a channel narrower from all around: airways, blood vessels, a gripped tube. Restrict keeps the imposed limit — re- plus stringere — holding something within bounds someone set: a rule, a quota, a permission. The everyday tell is authorship. A cold constricts a blood vessel (no one decides it; the tissue narrows); a government restricts imports (someone drew the line). And the two chain neatly — a constricted pipe restricts the flow through it — which is exactly why they blur.
constrict
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.
restrict
To restrict is to hold something inside limits — to cut down how much is allowed through, who may enter, or how far a thing can go. A diet restricts certain foods; a law restricts access; a narrow valve restricts a flow to a trickle. The point is throttling rather than stopping: what is restricted still exists, but only a permitted portion gets past. From the Latin restringere, 'to bind back', it shares its root with 'restrain' and 'strict'.
| constrict | restrict | |
|---|---|---|
| Meaning | squeeze physically narrower | limit what is allowed or gets through |
| Nature | a physical grip, all around | a rule or boundary with an author |
| Acts on | vessels, airways, tubes, throats | access, amounts, freedoms, diets |
| Who decides | conditions — cold, fear, a hand | someone — a rule, a law, a policy |
| The relationship | the mechanism | the resulting or imposed limit |
| Nouns | constriction (a narrowed place) | restriction (a rule) |
The gripped hose and the tethered goat. Constrict is the hand on the hose: the tube itself is squeezed narrower, and the trickle downstream is the consequence. Restrict is the goat's rope: nothing about the goat is squeezed — it is simply held inside a boundary someone staked out. Ask whether something is physically narrowed or merely limited. Squeezed tighter around its girth: constrict. Held within set limits: restrict. A scarf constricts your neck; a dress code restricts what you wear.
constrict
- iCold air constricts the airways, which is why winter runs start with coughing.
- iiA tight collar constricts the dog's throat when it pulls.
- iiiFear constricted her chest until she could barely speak.
restrict
- iThe new rules restrict how much cash can be withdrawn in a day.
- iiA strict visa restricts where he can work.
- iiiThe diet restricts salt rather than calories.
The two chain so naturally — a constricted artery restricts blood flow — that keeping the mechanism (constrict) apart from the consequence (restrict) is the whole skill. The nouns keep the split too: a constriction is a narrowed place you could point to, a restriction is a rule with an author. Constrict's third look-alike, constrain, and its own tangle with contract are drawn on the pages in the 'Related' list below.
TOEFL biology writes the physical verb: airways and vessels constrict, and passages assume it. IELTS policy and social writing needs the imposed one: governments restrict imports, schools restrict phone use. The penalised error is using the body verb for a rule — 'the government constricted imports' pictures a squeezed pipe, not a policy. Keep the chain straight in science answers, too: the vessel constricts, so the flow is restricted — mechanism, then consequence, each with its own verb.