“A different kettle of fish” means a situation that has changed after a few days or a thing that has experienced a change after a few days or after some time and now it stands differently. It can also be used for people as well.
The origin of “a different kettle of fish” is traced back to Thomas Newte’s A Tour in England and Scotland published in 1785. It is stated to have mentioned it. There is another origin from Scotland, a newspaper Carlisle Patriot published in June 1889. It has mentioned this phrase as follows;
“To enable them to manage their own local affairs will not satisfy Irishmen. What they want is a very different kettle of fish.” Here the phrase has been used in the same meanings as explained above.
Examples in Sentences
Example #1: This phrase could be used as a metaphor for a situation “Now you cannot get this scholarship, for it was a different kettle of fish two days back. You are late now.
Example #2: The suggestion you have presented today is a different kettle of fish from your previous ones.
Example #3: Playing for your team seems to me a different kettle of fish now.