English Reference
Adjective

acidic

adj.
B2 Upper Intermediate US /əˈsɪdɪk/ UK /ɐsˈɪdɪk/ acidic Geology

adj.having the sharp, sour taste or chemical properties of acid. You use this word for things like lemons, vinegar, or rain that can burn or dissolve other materials.

adj.having the chemical properties of an acid, such as a pH level below 7, a sour taste, or the ability to react with bases and metals.


SIMPLE

Lemons are very acidic fruits.

CONTEXTUAL

The acidic soil in this region makes it difficult to grow most vegetables without adding lime.

COMPLEX

The rapid decline of the coral reef was attributed to increasing ocean acidity, which dissolves the calcium carbonate structures essential for their survival.

The water is becoming more acidic as carbon from the air sinks into it.

Smithsonian Magazine· 28 Aug 2026

In these places, heat waves drive waters to be more acidic.

Phys.org· 24 Aug 2026

From acid + -ic. Doublet of acidy.

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

This entry
Level B2 · Upper Intermediate
Frequency Frequent
Updated