Blue moon and Forever and a day

Blue moon noun - A long or seemingly long period of time.

Forever and a day and blue moon are semantically related in long period of time topic. In some cases you can use "Forever and a day" instead a noun phrase "Blue moon".

Forever and a day adverb - For a very long or seemingly endless time.

Blue moon and forever and a day are semantically related in forever topic. You can use "Blue moon" instead a noun phrase "Forever and a day", if it concerns topics such as eternity. popular alternative