Wiktionary
jump blues
n. (context music English) A type of blues music with a strong rhythm, electric guitar, saxophone, and loud, raunchy singing. Considered to be the precursor to rock and roll.
Wikipedia
Jump blues
Jump blues is an up-tempo style of blues, usually played by small groups and featuring saxophone or brass instruments. It was popular in the 1940s and was a precursor of rhythm and blues and rock and roll. Appreciation of jump blues was renewed in the 1990s as part of the swing revival.
Usage examples of "jump blues".
He heard it over the radio, the DJ calling it swing when it was really just jump blues.