fed-up

The adjective "fed-up" originated in the late 19th to early 20th century as a colloquial expression, likely from the imagery of being fed (as with food or information) to the point of excess or satiety. The particle "up" is used in its completive sense, common in phrasal verbs, to indicate a state reached by the action of the verb. Thus, the literal sense of "having been fed completely" evolved metaphorically to describe a feeling of being overfull with annoyance, dissatisfaction, or boredom. This semantic shift from physical satiation to emotional or mental weariness is a classic example of metaphorical extension in informal English.

Structure: fed (past participle of 'feed') + up (adverb) - fed: From Old English 'fēdan' (to feed, nourish). In this compound, it functions as a past participle meaning "having been fed." - up: From Old English 'ūp' (upward, aloft). In this compound, it functions as an adverb indicating a state of completion or saturation.