unless
conjunctionUK /ənˈles/
US /ənˈles/
except if something happens.
We will go to the park unless it rains.
OTHER MEANINGS
2. except in the case that.
I won't call you unless I need help.
3. used to introduce a condition that must be met.
You can't enter unless you have a ticket.
4. except when.
The store is open daily unless it is a holiday.