Origin and history of constriction

c. 1300, streinen, "tie, bind, fasten, gird;" early 14c., "confine, restrain" (a body part, animal, etc.), senses now obsolete, from present-participle stem of Old French estreindre "bind tightly, clasp, squeeze," from Latin stringere (2) "draw tight, bind tight, compress, press together."

This is reconstructed to be from PIE root *streig- "to stroke, rub, press" (source also of Lithuanian strėgti "congeal, freeze, become stiff;" Greek strangein "twist;" Old High German strician "mends nets;" Old English streccian "to stretch;" German stramm, Dutch stram "stiff").

Strain is attested from late 14c. as "tighten; stretch, extend; make taut; stretch to the utmost tension," also, intransitive, "exert oneself, strive; exert a compelling force;" also "overexert (a body part), injure by overstretching."

The sense of "press through a filter, put (a liquid) through a strainer" to purify from extraneous matter is from late 14c. (implied early 14c. in strainer); that of "to stress beyond measure, carry too far, make a forced interpretation of" is from mid-15c. Related: Strained; straining.

Transitive strain at "make a difficulty of" (1580s) echoes Matthew xxiii.24 (strain at a gnat; Tyndale has the line as Ye blind guides, which strain out a gnat, and swallow a camel), in which the sense seems to be "will strain the liquor if they find (but) a gnat in it."

1732, "to cause to draw together by external force or influence;" 1759, "to draw together at any point by force or action," a back-formation from constriction, or else from Latin constrictus, past participle of constringere "compress" (see constrain).

A direct borrowing from Latin of the same word which, via French, became constrain. Earlier in the same sense was constringe (c. 1600). Related: Constricted; constricting.

word-forming element meaning "together, with," sometimes merely intensive; it is the form of com- used in Latin before consonants except -b-, -p-, -l-, -m-, or -r-. In native English formations (such as costar), co- tends to be used where Latin would use con-.