Engineering Dictionary of Capacitor Terms
"A", "B/C", "D", "E", "F", "G", "I/L",
"M/N/O", "P", "Q/R", "S", "T", "V/Z"

Variable Capacitor: An adjustable Capacitor. A capacitor that does not have a fixed value. A trimmer capacitor is also a variable capacitor but only used when small or subtle changes are required. The physical size of these trimmer capacitors are also small and require a flat-head screw driver to make adjustments.

Panel Mount Variable Capacitor
Panel Mount Trimmer Capacitor

Through hole parts are used as examples, but surface mount components are also possible. Ease of use is not necessarily a consideration when you also consider things like cost, size and the number of times the device will be used. Again the trimmer is only meant to be a minor adjustment, and many times an adjustment that might only be made once.

Board Mount Variable Capacitor
3-Terminal Trimmer Capacitor

Vertical Through-hole Variable Capacitor
Through Hole Trimmer Capacitor
PC motherboard

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