increase make bigger or more; "The boss finally increased her salary"; "The university increased the number of students it admitted"
modify,
alter,
change make less severe or harsh or extreme; "please modify this letter to make it more polite"; "he modified his views on same-gender marriage"
suppress reduce the incidence or severity of or stop; "suppress a yawn"; "this drug can suppress the hemorrhage"
mitigate make less severe or harsh; "mitigating circumstances"
minify -
To reduce in apparent size, as for example objects viewed through a lens or mirror shaped so as to increase the field of view, such as a convex or aspheric mirror or a Fresnel lens.