Definition of "nimravid"

The earliest nimravids, Dinictis and Hoplophoneus of western North America, were already saber-toothed, with large, serrated, and laterally compressed upper canine teeth and a protective bony flange on the mandible.

2006, Kenneth D. Rose, The Beginning of the Age of Mammals, unnumbered page

Feliformia includes the more catlike carnivorans: nimravids and barbourofelids (the extinct, so-called false sabertooths, though "false" alludes to their relationship to sabertooth felids, because their upper canine teeth were quite large in some forms), felids (true cats), herpestids (mongooses), viverrids (civets), and hyaenids (hyenas), among others. […] The nimravids survived into the Miocene (Tseng et al., 2010), and some of their members early developed a large size and large canine saber teeth.

2013, Richard A. Fariña, Sergio F. Vizcaíno, Gerry De Iuliis, Megafauna: Giant Beasts of Pleistocene South America, page 125

The nimravids are not known after the Miocene. Features that distinguish nimravids from felids include the lack of an auditory bulla in most species and the absence of a cruciate sulcus (a conspicuous, deep groove) on the brain.

2013, Terry A. Vaughan, James M. Ryan, Nicholas J. Czaplewski, Mammalogy, page 287