modify has definitions from the field of grammar
1
[ verb ] make less severe or harsh or extreme

Examples

"please modify this letter to make it more polite" "he modified his views on same-gender marriage"

Used in print

(Frank Oppenheimer, "Science and Fear-- A Discussion...)

Apparently the population as_a_whole eventually acquires enough confidence in the explanations of the scientists to modify its procedures and its fears .

(Raymond C. Binder et al., editors, Proceedings...)

In plasma generators the superimposed forced convection may modify the picture somewhat .

The gas flow through a plasma generator will modify these conditions ; however , the anode is still the part receiving the largest heat flux .

Gas injection through a porous anode ( transpiration cooling ) not_only feeds_back the energy transferred to the anode by the above mentioned processes , but also modifies the conditions in the arc itself .

(Harry H. Hull, "The Normal Forces and Their Ther...)

There is one exception to the above statement as has been pointed_out , and that is that fluids can relax by flowing into fields of lower rates of shear , so the statement should be modified by stating that the mechanics are similar .

2
[ verb ] (grammar) add a modifier to a constituent

Synonyms

qualify

Used in print

(Ralph B. Long. The Sentence and Its Parts: A...)

In the second sentence if drinking water is a gerundial clause and without drinking water is roughly equivalent in meaning to unless I drink water , there will be stronger stress on water than on drinking ; but if drinking is a gerundial noun modifying water and without drinking_water is equivalent_to without water for drinking , there will be stronger stress on drinking than on water .

3
[ verb ] cause to change; make different; cause a transformation

Synonyms

change alter

Examples

"The advent of the automobile may have altered the growth pattern of the city" "The discussion has changed my thinking about the issue"

Related terms

leave make put lend better fill increase bring prepare enable affect end strengthen adjust unclutter clean cool transform switch convert shape dry damage affect heat turn transform bring reduce mix set emphasize tighten awaken translate color invert obscure straighten decorate weaken clarify make complicate loosen convert right mark centralize empty suspend wet simplify renew develop civilize decrease break_down make_possible estrange remodel demythologize boil worsen form neutralize sensitize magnetize thicken mince insulate habituate nationalize stabilize confuse polarize stain blind activate charge harmonize stiffen draw obscure touch complicate lift shift cut suspend inform iodinate counterchange depersonalize flatten oxidize decentralize ripen communize Europeanize saturate reconstruct naturalize purify revolutionize ease_up assimilate brighten check corrupt commute democratize liberalize shake blur capture humanize humble alter disqualify automatize widen dirty restore sophisticate glorify contaminate personalize spice outmode urbanise fatten urbanize sputter prostrate harshen end cook animize edit extend dull warm tame conventionalize freeze parallel poison convert invert disable archaize unscramble sharpen sharpen customize demagnetize blunt spike refine supercharge unite age socialize coarsen round_off vascularise internationalize Europeanize antiquate antique Americanize bestialize anglicize Frenchify soften sober decrepitate denationalize acerbate naturalize denaturalize even denaturalize destabilize suburbanize etiolate cry equal detransitivize transitivize full familiarize desensitize diversify deaden disorder discolor dissimilate liquefy

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