also: しんぐるす
Old rulebooks say 単試合, but nowadays we say シングルス.
Rare kanji spelling for 'singles' in sports; the loanword シングルス is overwhelmingly more common.
Standard modern term for singles in tennis, badminton, etc.
Compound of 単 (single) and 試合 (match, game). The exact origin is uncertain, but it appears to be a native coinage for the concept of singles in sports, later largely replaced by the loanword シングルス.