[Chemistry] a salt or ester of acetic acid, containing the anion CH3COO− or the group —OOCCH3.
2. [ mass noun] — cellulose acetate, especially as used to make textile fibres or plastic[as modifier] • acetate silk.
3. [ count noun] — a transparency made of cellulose acetate film. 4. [ count noun] — a sample version of a recording disc cut by a stylus rather than formed by a stamper, and coated with cellulose acetate.