acidity

noun

acid·​i·​ty ə-ˈsi-də-tē 

a-

plural acidities

1

: the quality, state, or degree of being acid

2

: the state of being excessively acid

Synonyms of acidity

• bitterness
• bite
• edge

Examples of acidity in a Sentence

detected a certain acidity in the way he responded

the acidity of their relationship was well known to their mutual acquaintances

Recent Examples on the Web

The acidity in bird droppings can corrode metal, stain wood, dull finishes, and etch paint if left too long. — Karen Brewer Grossman, Southern Living, 18 July 2026

That shift in acidity translated into a much more efficient conversion of nitrate to nitric oxide. — Jennifer Klump, Verywell Health, 17 July 2026

Like the perfect peach, your fruit salad should dance between acidity and sweetness. — Cooking Editor, Los Angeles Times, 10 July 2026

That has raised ocean acidity—a direct result of CO2 absorption—by 30%. — Jeffrey Kluger, Time, 9 July 2026

Word History

Etymology

borrowed from French & Late Latin; French acidité, going back to Middle French, borrowed from Late Latin aciditāt-, aciditās, from Latin acidus "sour, acid entry 2" + -itāt-, -itās -ity

First Known Use

1615, in the meaning defined at sense 1

Rhymes for acidity

• aridity
• avidity
• cupidity
• fluidity
• humidity
• liquidity
• lucidity
• morbidity
• placidity
• rancidity
• rapidity
• rigidity

Kids Definition

acidity

noun

acid·​i·​ty ə-ˈsid-ət-ē 

a-

plural acidities

1

: the quality, state, or degree of being acid

2

: the state of being extremely acid

Medical Definition

acidity

noun

acid·​i·​ty ə-ˈsid-ət-ē, a- 

plural acidities

1

: the quality, state, or degree of being sour or chemically acid

the acidity of lemon juice

2

: the quality or state of being excessively or abnormally acid : hyperacidity