Spoilsport is a compound of spoil (from Latin spoliare 'to plunder') + sport (from Old French desport 'pastime, amusement'), literally one who ruins others' fun. The historical chain includes Latin spoliare and Old French desport. Older glosses in the chain include "to plunder" and "pastime, amusement", which help explain the semantic range of the modern word. Morphologically, spoilsport is best read as compound and borrowing, yielding an English noun shaped by both form history and later usage. In current English it functions as a noun, with the sense "a person who spoils the pleasure or enjoyment of others". related forms include spoil and sport. The result is an English noun whose etymology preserves the older forms while supporting the word's specialized modern meaning.