"inactive, indolent; loath, reluctant, unwilling," Middle English swere, also "grievous, sad," from Old English swær "heavy; sad; oppressive; grievous; sluggish, inactive, weak;" cognate with Old Frisian swer, Old Saxon swar, Middle Dutch swaer, Dutch zwaar, Old High German suari, "heavy," German schwer "difficult," Gothic swers "honored, esteemed," literally "weighty."

This is probably from a PIE root *sehro- "slow, heavy" (source also of Lithuanian sveriu, sverti "to weigh, lift," svarus "heavy, weighty").

The physical senses did not survive Old English and the word died out after Middle English.

Middle English hevili, figuratively, "burdensomely, oppressively; apathetically, with indifference," also "intensely," from Old English hefiglice "violently, intensely; sorrowfully; with slow or sluggish movement," from hefig (see heavy (adj.)) + -ly (2).

The meaning "with much weight" is attested from early 14c. From c. 1400 as "with grief or sorrow."

Middle English hevinesse, from Old English hefigness "state of being heavy, weight; burden, affliction; dullness, torpor;" see heavy (adj.) + -ness. Chaucer has heavity for "sadness."

"durable, strong," 1903; see heavy (adj.) + duty.

also heavyhanded, 1630s, originally "weary" or "clumsy;" from heavy (adj.) + -handed. Sense of "overbearing" is recorded by 1873.

also heavy-weight, noun and adjective, 1857 of horses; 1877 of fighters; from heavy (adj.) + weight. Figuratively, in reference to importance, from 1928.

also topheavy, 1530s, figurative ("liable to fall or fail through instability of proportions); 1640s literal, "over-weighted on top, having the top disproportionately heavy;" from top (n.1) + heavy (adj.). Also, colloquially, "drunk" (1680s). Related: Topheaviness.

Proto-Indo-European root meaning "to grasp."

It might form all or part of: accept; anticipate; anticipation; behave; behoof; behoove; cable; cacciatore; caitiff; capable; capacious; capacity; capias; capiche; capstan; caption; captious; captivate; captive; captor; capture; case (n.2) "receptacle;" catch; catchpoll; cater; chase (n.1) "a hunt;" chase (v.) "to run after, hunt;" chasse; chasseur; conceive; cop (v.) "to seize, catch;" copper (n.2) "policeman;" deceive; emancipate; except; forceps; gaffe; haft; have; hawk (n.); heave; heavy; heft; incapacity; inception; incipient; intercept; intussusception; manciple; municipal; occupy; participation; perceive; precept; prince; purchase; receive; recipe; recover; recuperate; sashay; susceptible.

It might also be the source of: Sanskrit kapati "two handfuls;" Greek kaptein "to swallow, gulp down," kope "oar, handle;" Latin capax "able to hold much, broad," capistrum "halter," capere "to grasp, lay hold; be large enough for; comprehend;" Lettish kampiu "seize;" Old Irish cacht "servant-girl," literally "captive;" Welsh caeth "captive, slave;" Gothic haban "have, hold;" Old English hæft "handle," habban "to have, hold."