corrupt, debase, or make impure by adding a foreign or inferior substance; often by replacing valuable ingredients with inferior ones; "adulterate liquor"
make (alcohol) unfit for drinking without impairing usefulness for other purposes
modify (as a native protein) especially by heat, acid, alkali, or ultraviolet radiation so that all of the original properties are removed or diminished
add nonfissionable material to (fissionable material) so as to make unsuitable for use in an atomic bomb
(of quantities) imprecise but fairly close to correct; "lasted approximately an hour"; "in just about a minute"; "he's about 30 years old"; "I've had about all I can stand"; "we meet about once a month"; "some forty people came"; "weighs around a hundred pounds"; "roughly $3,000"; "holds 3 gallons, more or less"; "20 or so people were at the party"