The word 'taster' is a straightforward agent noun formation from the verb 'taste'. The verb 'taste' entered English from Old French taster, which meant 'to touch, try, or taste', a meaning that blended the physical act of touching with the specific sense of testing flavor. This Old French term is of Germanic origin, likely from a Frankish source akin to the Old English tæstan, meaning 'to touch or test'. By adding the native agent suffix '-er', the word 'taster' was created to denote a person (or later, an object) whose primary function is to perform the act of tasting, specifically to test quality or provide a sample experience.

Structure: tast (to perceive flavor) + er (agent suffix) - tast: From Old French taster (to touch, try, taste), of Germanic origin; related to Old English tæstan (to touch, test). The core sense is 'to test by touching or trying'. - er: A native English agent noun suffix, from Old English -ere, used to form nouns denoting a person or thing that performs the action of the verb.