Heavy metal music and Rock and roll

Heavy metal music noun - Loud and harsh sounding rock music with a strong beat; lyrics usually involve violent or fantastic imagery.

Rock and roll and heavy metal music are semantically related. In some cases you can use "Rock and roll" instead a noun phrase "Heavy metal music".

Rock and roll noun - A genre of popular music originating in the 1950s; a blend of black rhythm-and-blues with white country-and-western.

Heavy metal music and rock and roll are semantically related. Sometimes you can replace phrase "Heavy metal music" with "Rock and roll", this phrases are similar.