kosketin

Kosketin is a Finnish noun meaning a key or touch-sensitive element on a keyboard. In everyday usage it most often denotes a key on a keyboard instrument, such as a piano or organ, which the player depresses to produce a tone. The term derives from the verb koskea, to touch, reflecting the act of touching a key to initiate sound. In musical contexts, kosketin refers to any individual key and, by extension, to the keyboard as a whole, including discussions of its range and layout.

In a broader technical sense, kosketin can also denote an electrical contact or switch contact—an element that closes a circuit when pressed or touched. In electronics and device manuals, kosketin is sometimes used to describe such contact points, though more specific terms like kosketin (contact) or other words may be employed depending on context.

In Finnish, more general terms for input devices on electronic equipment include näppäin for a key and näppäimistö for a keyboard. Kosketin is therefore most common in musical language and in technical contexts referring to physical touch points or contacts, rather than everyday computer keyboards. Kosketinsoitin is a compound form used to refer to a keyboard instrument, such as a piano or synthesizer, where the keys are the primary interface.