Meaning of “mould” - Learner’s Dictionary

mould

noun UK (US mold) uk us /məʊld/
SUBSTANCE [ U ]

a green or black substance that grows in wet places or on old food

CONTAINER [ C ]

a container that is used to make something in a particular shape:

a chocolate mould

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