Expressions used in Everyday Spoken English in Social and Professional contexts
When you 'let off steam' or 'blow off steam' it means to do something in order to help manage strong feelings emotions or a large amount of energy. Usually, when you 'let off steam' or 'blow off steam' you are doing something constructive rather than behaving in a way that expresses your anger or frustration or another negative feeling. This is a casual expression usually used in social contexts.