phosphoric acid

noun

1

: a syrupy or deliquescent tribasic acid H₃PO₄ used especially in preparing phosphates (as for fertilizers), in rust-proofing metals, and especially formerly as a flavoring in soft drinks

called also orthophosphoric acid

2

: a compound (such as pyrophosphoric acid or metaphosphoric acid) consisting of phosphate groups linked directly to each other by oxygen

Examples of phosphoric acid in a Sentence

Recent Examples on the Web

Kidney Disease Some studies have suggested that the artificial sweeteners and high levels of phosphoric acid found in many diet sodas could contribute to kidney damage over time. —Cristina Mutchler, Verywell Health, 3 Feb. 2025

Electronic grade phosphoric acid is used as an etching agent in semiconductor manufacturing. —Claire Osborn, Austin American-Statesman, 29 July 2024

This is because jarred garlic is often pasteurized (heated to kill unwanted microorganisms) and it’s typically made with additives like citric acid and phosphoric acid. —Sam Stone, Bon Appétit, 6 Oct. 2023

Municipal American water treatment often involves chlorine, ammonia, fluoride, and phosphoric acid, with the latter acting as a defense against other contaminants like bacteria. —Jon Stojan, USA TODAY, 19 Aug. 2023

Word History

First Known Use

1765, in the meaning defined at sense 1

Rhymes for phosphoric acid

• antacid
• placid

Kids Definition

phosphoric acid

noun

phos·​phor·​ic acid

fäs-ˌfȯr-ik-,

-ˌfär-

: any of several oxygen-containing acids of phosphorus

Medical Definition

phosphoric acid

noun

1

: a syrupy or deliquescent tribasic acid H₃PO₄ used especially in preparing phosphates (as for fertilizers), in rust-proofing metals, and especially formerly as a flavoring in soft drinks

called also orthophosphoric acid

2

: a compound (as pyrophosphoric acid or metaphosphoric acid) consisting of phosphate groups linked directly to each other by oxygen