Once and for all and Swan song

Once and for all adverb - In a conclusive way.

Swan song and once and for all are semantically related. In some cases you can use "Swan song" instead an adjective phrase "Once and for all".

Swan song noun - A final performance or effort (especially before retirement).

Once and for all and swan song are semantically related. Sometimes you can use "Once and for all" instead an adjective phrase "Swan song".