*sāwel-, Proto-Indo-European root meaning "the sun." According to Watkins, the *-el- in it originally was a suffix, and there was an alternative form *s(u)wen-, with suffix *-en-, hence the two forms represented by Latin sol, English sun.
It forms all or part of: anthelion; aphelion; girasole; heliacal; helio-; heliotrope; helium; insolate; insolation; parasol; parhelion; perihelion; Sol; solar; solarium; solstice; south; southern; sun; Sunday.
It is the hypothetical source of/evidence for its existence is provided by: Sanskrit suryah, Avestan hvar "sun, light, heavens;" Greek hēlios; Latin sol "the sun, sunlight;" Lithuanian saulė, Old Church Slavonic slunice; Gothic sauil, Old English sol "sun;" Old English swegl "sky, heavens, the sun;" Welsh haul, Old Cornish heuul, Breton heol "sun;" Old Irish suil "eye;" Avestan xueng "sun;" Old Irish fur-sunnud "lighting up;" Old English sunne German Sonne, Gothic sunno "the sun."
*dhē-, Proto-Indo-European root meaning "to set, put."
It forms all or part of: abdomen; abscond; affair; affect (v.1) "make a mental impression on;" affect (v.2) "make a pretense of;" affection; amplify; anathema; antithesis; apothecary; artifact; artifice; beatific; benefice; beneficence; beneficial; benefit; bibliothec; bodega; boutique; certify; chafe; chauffeur; comfit; condiment; confection; confetti; counterfeit; deed; deem; deface; defeasance; defeat; defect; deficient; difficulty; dignify; discomfit; do (v.); doom; -dom; duma; edifice; edify; efface; effect; efficacious; efficient; epithet; facade; face; facet; facial; -facient; facile; facilitate; facsimile; fact; faction (n.1) "political party;" -faction; factitious; factitive; factor; factory; factotum; faculty; fashion; feasible; feat; feature; feckless; fetish; -fic; fordo; forfeit; -fy; gratify; hacienda; hypothecate; hypothesis; incondite; indeed; infect; justify; malefactor; malfeasance; manufacture; metathesis; misfeasance; modify; mollify; multifarious; notify; nullify; office; officinal; omnifarious; orifice; parenthesis; perfect; petrify; pluperfect; pontifex; prefect; prima facie; proficient; profit; prosthesis; prothesis; purdah; putrefy; qualify; rarefy; recondite; rectify; refectory; sacrifice; salmagundi; samadhi; satisfy; sconce; suffice; sufficient; surface; surfeit; synthesis; tay; ticking (n.); theco-; thematic; theme; thesis; verify.
It is the hypothetical source of/evidence for its existence is provided by: Sanskrit dadhati "puts, places;" Avestan dadaiti "he puts;" Old Persian ada "he made;" Hittite dai- "to place;" Greek tithenai "to put, set, place;" Latin facere "to make, do; perform; bring about;" Lithuanian dėti "to put;" Polish dziać się "to be happening;" Russian delat' "to do;" Old High German tuon, German tun, Old English don "to do."
It forms all or part of: abscissa; conscience; conscious; ecu; escudo; escutcheon; esquire; nescience; nescient; nice; omniscience; omniscient; plebiscite; prescience; prescient; rescind; rescission; science; scienter; scilicet; sciolist; scission; schism; schist; schizo-; schizophrenia; scudo; sheath; sheathe; sheave (n.) "grooved wheel to receive a cord, pulley;" shed (v.) "cast off;" shin (n.) "fore part of the lower leg;" shingle (n.1) "thin piece of wood;" shit (v.); shive; shiver (n.1) "small piece, splinter, fragment, chip;" shoddy; shyster; skene; ski; skive (v.1) "split or cut into strips, pare off, grind away;" squire.
It is the hypothetical source of/evidence for its existence is provided by: Sanskrit chindhi, chinatti "to break, split up;" Avestan a-sista- "unsplit, unharmed," Greek skhizein "to split, cleave, part, separate;" Latin scindere "to cut, rend, tear asunder, split;" Armenian c'tim "to tear, scratch;" Lithuanian skiesti "to separate, divide;" Old Church Slavonic cediti "to strain;" Old English scitan, Old Norse skita "to defecate;" Old English sceað, Old High German sceida "sheath;" Old Irish sceid "to vomit, spit;" Welsh chwydu "to break open."
It forms all or part of: bale (n.) "large bundle or package of merchandise prepared for transportation;" baleen; ball (n.1) "round object, compact spherical body;" balloon; ballot; bawd; bold; bole; boll; bollocks; bollix; boulder; boulevard; bowl (n.) "round pot or cup;" bulk; bull (n.1) "bovine male animal;" bullock; bulwark; follicle; folly; fool; foosball; full (v.) "to tread or beat cloth to cleanse or thicken it;" ithyphallic; pall-mall; phallus.
It is the hypothetical source of/evidence for its existence is provided by: Greek phyllon "leaf," phallos "swollen penis;" Latin flos "flower," florere "to blossom, flourish," folium "leaf;" Old Prussian balsinis "cushion;" Old Norse belgr "bag, bellows;" Old English bolla "pot, cup, bowl;" Old Irish bolgaim "I swell," blath "blossom, flower," bolach "pimple," bolg "bag;" Breton bolc'h "flax pod;" Serbian buljiti "to stare, be bug-eyed;" Serbo-Croatian blazina "pillow."
An extended form of the root, *bhelgh- "to swell," forms all or part of: bellows; belly; bilge; billow; bolster; budget; bulge; Excalibur; Firbolgs.
An extended form of the root, *bhleu- "to swell, well up, overflow," forms all or part of: affluent; bloat; confluence; effluent; effluvium; efflux; fluctuate; fluent; fluid; flume; fluor; fluorescence; fluoride; fluoro-; flush (v.1) "spurt, rush out suddenly, flow with force;" fluvial; flux; influence; influenza; influx; mellifluous; phloem; reflux; superfluous.