Rootsrock is what it says on the tin: rock music with roots. That means rock music that borrows from traditional genres or is a blend of traditional music and rock. The word roots is often used to signify the original form of a particular genre. For example folk and blues. To complicate matters, the concept roots music is also used across many styles. The term roots rock was first coined in USA to denote music that drew on rock music's origins in blues, folk and country.
For instance, country rock, southern rock and, to a certain extent, progressive rock and punk rock, too – wherever the music refers back to basics, but with the standard electric band line-up. A classic example of roots rock in a southern rock guise is The Allman Brothers Band and, in more recent times, Jason Isbell, The Mavericks, Larkin Poe, Calexico, Los Lobos. In retrospect, we can call Little Feat and The Band roots rock.