ENGLISH
REFERENCE

acid

n. C / U
C1 Advanced Oxford US //ˈæsəd// UK //ˈæsɪd// acid Slang

n. a chemical substance that tastes sour and can burn your skin or dissolve metal. You also find weak versions in things like lemons or vinegar.

n. a chemical substance that neutralises alkalis and dissolves some metals; typically characterised by a sour taste and the ability to turn blue litmus paper red.


SIMPLE

The acid in the lemon makes the juice taste very sour.

CONTEXTUAL

Scientists wear protective gloves when handling strong acid to prevent chemical burns on their skin.

COMPLEX

The gradual erosion of the limestone statues was accelerated by acid rain, which reacts with the calcium carbonate to dissolve the fine details of the carvings.

Synonyms
Origin

Etymology tree Proto-Indo-European *h₂eḱ-der. Latin aceō Proto-Indo-European *dʰeh₁-der. Latin -idus Latin acidusbor. French acidebor. English acid From French acide, from Latin acidus (“sour, acid”), from aceō (“to be sour”). Doublet of agita.

Usage

Uncountable when referring to the substance in general; countable when referring to specific chemical types or laboratory samples.

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