Meaning of “jumper” - Learner’s Dictionary

jumper

noun [ C ] uk us /ˈdʒʌmpər/
WARM CLOTHING UK (UK/US sweater)

A2 a warm piece of clothing that covers the top of your body and is pulled on over your head

DRESS US (mainly UK pinafore)

a loose dress with no sleeves that is worn over other clothes such as a shirt

(Definition of “jumper” from the Cambridge Learner’s Dictionary © Cambridge University Press)