Sideline

Part of speech: noun, verb

Pronunciation: /ˈsaɪdlaɪn/

Definitions

1. An activity done in addition to a main job ; a line marking the side boundary of a playing field ; to remove someone from active involvement in an event or role
2. A secondary job or source of income separate from primary work ; the boundary line along the side of sports fields ; to take out of active duty or participation temporarily or permanently
3. A supplementary pursuit alongside a principal career ; a line on the edge of a sports playing area indicating limits ; to exclude or bench a player or participant from action

Etymology: "Sideline" is a plain compound: "side" plus "line," with the sense of a line running along the edge of something. The most useful thread is the sporting one. A sideline is the boundary line marking the long edge of a playing field, and the people and activities that happened just beyond that line were, by extension, the ones not in the main action. The noun for an activity pursued alongside one's main job came from the idea of something pursued from the edge of the field rather than in the centre of play. The noun, the verb "to sideline" (to remove someone from active participation, or to set them aside), and the extra-paid-work sense all grow from that same image. Putting someone on the sidelines means keeping them out of the game, while a sideline job is one you do off to the side of your primary occupation. The compound itself is transparent: the meaning of each part maps directly onto the whole.

Synonyms: periphery, margin, outskirts, secondary, fringe

Antonyms: center, core, main, focus, priority