1 acid /ˈæsəd/ noun
plural acids
1 acid
plural acids
Learner's definition of ACID
chemistry : a chemical with a sour taste that forms a salt when mixed with a base
◊ An acid has a pH of less than 7. Very strong acids are able to burn holes in things.
compare 1base 6, ph
[noncount] slang : lsd
2 acid /ˈæsəd/ adjective
2 acid
Learner's definition of ACID
[more acid; most acid]
always used before a noun : of, relating to, or having the qualities of an acid
: sharp, strong, and critical in tone

— acidity

ˈsɪdəti/ noun [noncount]

— acidly

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