The term paraphrase in music seems quite clearly defined.
Right coming from searching another term for the fill-ins, echo-ing, answering in a musical dialog of 2 instruments, a singer and piano or guitar, I proposed the term "paraphrasing". Now I've found paraphrasing used in of other answers and comments.
Now in opposite or better saying in difference to the noun paraphrase and the verb to paraphrase I propose to use the gerund form paraphrasing (adapted from the use by therapists when counselling clients) to distinguish the short comments of an instrument at the phrases of the lead singer.
I'm not sure whether there is evidence for a definition of paraphasing. If yes, thank you for answering.