A colorless pungent fuming vesicatory liquid acid HCOOH found naturally in ants and many plants or made catalytically from carbon monoxide and steam; used in finishing textiles and paper and in the manufacture of insecticides and fumigants WordNet 3.0 & Open English WordNet

Formic acid, systematically named methanoic acid, is the simplest carboxylic acid, and has the chemical formula HCOOH and structure H−C−O−H. It is an important intermediate in chemical synthesis and occurs naturally, most notably in some ants. Wikipedia

A chemical compound secreted by ants for defense Wikipedia Disambiguation

Chemical compound Wikidata

The simplest carboxylic acid, HCOOH, a colourless, corrosive liquid with a sharp odour; it is present in the stings of ants, bees and nettles, and is prepared industrially by the oxidation of methanol or formaldehyde; it has some industrial uses, and its esters, the formates are used in perfumes. Wiktionary

Methanoic acid. Wiktionary (translation)