Question

what is the meaning of the idiom "once in a blue moon".
1 a very rare case
2 frequently happening case
3 an impossible case​

Answer 1

Answer:

2 frequently happening case

Explanation:

When we say that something happens once in a blue moon, what we mean is that it happens very rarely. History of expression: The 'moon' in this expression does, in fact, refer to the real moon when it is full.

Answer 2

Answer:

the meaning of the idom "once in a blue moon" is

option (1) a very rare case