pyjamas

Concise Oxford English Dictionary © 2008 Oxford University Press:
pyjamas /pəˈʤɑːməz/ (US pajamas)

▶plural noun

• 1 a jacket and loose trousers for sleeping in.

• 2 loose trousers with a drawstring waist, worn by both sexes in some Asian countries.

– origin C19: from Urdu and Pers., from pāy ‘leg’ + jāma ‘clothing’.