acetate

Any ester or salt of acetic acid.

[…] to pad a piece in diluted acetate of alumine to obtain a pale lemon ground […]

Cellulose acetate.

Performers use acetate because eyelash glue is not available. They create eyelashes out of horse hair or cut from carbon paper. Their nails are glued on with a shoe adhesive.

A transparent sheet used for overlays, whether of cellulose acetate or (loosely) any macroscopically similar plastic.

Near-synonym: gel

In full acetate disc: a disc of aluminium covered in a wax used to make demonstration copies of a phonograph record.

Acetates are a relic of the days before cassettes, DAT, and recordable CDs came into widespread use in recording studios. Manufactured from aluminum, and coated in a thin sheet of vinyl, they were produced to allow the concerned parties to hear how a particular version of a recording would sound outside the studio, on their home hi-fi, for example.