What is the meaning of Trimmer?

comparative form of trim: more trim

One who trims, arranges, fits, or ornaments.

A device used to trim.

A member of the crew who trims the sails.

Someone who fluctuates between opposing factions, political parties etc., according to current interest, a flip-flopper.

A beam into which are framed the ends of headers in floor framing, as when a hole is to be left for stairs, or to avoid bringing joists near chimneys.

A person employed to rearrange the coal in the hold of a vessel, so that it fills the vessel without forming a conical blockage.

A device for storing coal in gradually increasing piles made by building up at the point of the cone or top of the prism.

A float bearing a baited hook and line, used in fishing for pike.

An adjustable electrical component.

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Wikipedia

One who or that which trims, or rebukes or reproves; a scold.

a trimmer (device used to trim)

Source: wiktionary.org