MEK
Methyl-ethyl-ketone is an organic chemical solvent that is soluble in water and is used as a solvent for vinyl and nitrocellulose films. MEK is an efficient cleaner for preparing surfaces for priming or painting.
Aviation Maintenance Technician Handbook — Airframe, p. G-22
Also defined in 1 more source
Methul ethyl ketone. A volatile, water soluble, organic chemical compound that is used as a solvent to remove oily contaminants from ignition system components.
Aviation Maintenance Technician Handbook — Powerplant, p. G-18