glacial acetic acid vs. acetic acid

acetic acid of at least 99.5 percent concentration, solidifying at 16.7°C.

a colorless, pungent, water-miscible liquid, C 2 H 4 O 2 , the essential constituent of vinegar, produced by oxidation of acetaldehyde, bacterial action on ethyl alcohol, the reaction of methyl alcohol with carbon monoxide, and other processes: used chiefly in the manufacture of acetate fibers and in the production of numerous esters that are solvents and flavoring agents.