con- + stringere "to draw tight" (see strain (v.))

FORCE, COMPEL, COERCE, CONSTRAIN, OBLIGE mean to make someone or something yield.

FORCE is the general term and implies the overcoming of resistance by the exertion of strength, power, or duress.

e.g. forced to flee for their lives

COMPEL typically suggests overcoming of resistance or unwillingness by an irresistible force.

e.g. compelled to admit my mistake

COERCE suggests overcoming resistance or unwillingness by actual or threatened violence or pressure.

e.g. coerced into signing over the rights

CONSTRAIN suggests the effect of a force or circumstance that limits freedom of action or choice.

e.g. constrained by conscience

OBLIGE implies the constraint of necessity, law, or duty.

e.g. felt obliged to go

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compel or force (someone) toward a particular course of action:

«…することを» 〈人･物など〉に強いる «to do» (!しばしば受け身で)

e.g. children are constrained to work in the way the book dictates.

(usually as adjective constrained) cause to appear unnaturally forced, typically because of embarrassment:

e.g. he was acting in a constrained manner.

severely restrict the scope, extent, or activity of:

〈人･物など〉を束縛する, 押し込める

e.g. agricultural development is considerably constrained by climate

«…を» 〈人〉に制約する «from (doing)»

e.g. we can constrain data access.

archaic bring about (something) by compulsion:

e.g. Calypso in her caves constrained his stay.

literary confine forcibly; imprison.

constrainedly | kənˈstrānədlē | adverb

Middle English: from Old French constraindre, from Latin constringere ‘bind tightly together’.