Wiktionary
methyl isobutyl ketone
n. (context organic compound English) The aliphatic ketone (CH3)2CH-CH2-CO-CH3, that is used as a solvent
Wikipedia
Methyl isobutyl ketone
Methyl isobutyl ketone (MIBK) is the organic compound with the formula (CH)CHCHC(O)CH. This colourless liquid, a ketone, is used as a solvent for gums, resins, paints, varnishes, lacquers, and nitrocellulose.