keep it under the hat
It means "no matter what happens." It is pretty self-explanatory - no matter what happens, you are going to follow through on your plans.
This expression means real and simple.
This is not an idiom because it means just what it says. If something is a bargain, then it is always a bargain. It doesn't matter what the circumstances are.
It means to get married.
It means that is the essence of it. Similar to the expression 'in a nutshell'.
In the USA it means "To get angry" In the UK it means "To get drunk"
This is slang - it means your spouse.
i believe it means: to hope that...
It means that it is extremely easy.
The idiomatic expression for "advanced in years" is "getting on in age."
It means just what it sounds like - no matter what the cost, do it.
The expression is not idiomatic. It means exactly what it says. To be sent on ( or for) errands means to be out on a shopping trip, or such like, for someone. Mother sent me on errands to the grocery store and the dry cleaners.