Accretion

Part of speech: noun

Pronunciation: /əˈkɹiːʃn̩/

Definitions

1. The gradual accumulation of material through successive addition or adhesion, or the process by which celestial bodies grow larger by collecting surrounding matter
2. a gradual process in which material builds up layer by layer through repeated attachment or accumulation of external matter
3. the slow growth that occurs when small particles or fragments stick together and combine into larger masses over time

Etymology: Before it named the slow buildup of coral reefs or river deltas, "accretion" was a plain Latin verb of growth. Its ancestor, "accrēscere," combined "ad-" (here meaning something like "toward," often intensifying the sense) with "crēscere," "to grow," the same root that gives English "crescent" and "increase." The Latin noun "accrētiō" simply meant an increase or increment, built by adding the common suffix "-tiō," which turns actions into nouns. English borrowed the Latin noun directly rather than inheriting it through French, so "accretion" is a learned borrowing, and it sits as a doublet of "accrue" and "increase," which came into English by other routes. Its original English sense was broad: any growth by addition, not specifically geological or biological.

Synonyms: accumulation, increase, growth

Antonyms: reduction, decrease