These fishes are appropriately named for their oversized, recurved palatine teeth redolent of the saber-toothed cats. The family name "Evermannellidae" was given in honour of Dr. Barton Warren Evermann, a noted ichthyologist, naturalist and director of the California Academy of Sciences.
There is a single high dorsal fin (with 10–13 rays) originating slightly before the thoracic pelvic fins. The anal fin (26–37 rays) is the largest of the fins, and runs along the posterior half of the fish, tapering in height towards the emarginate caudal fin. A small adipose fin is also present. The pectoral fins (11–13 rays) are positioned rather low on the body. All fins are spineless and lightly pigmented in shades of brown.
Sabertooth fish are usually a drab, light to dark brown when preserved; however, a brassy green iridescence is seen on the flanks, cheeks, and ocular region of well-preserved specimens. The naked skin is easily torn. The Atlantic sabertooth (Coccorella atlantica) is the largest species, at up to 18.5 centimetres standard length.
Their distensible stomachs allow sabertooth fish to swallow prey larger than themselves; their recurved teeth likely function in a manner similar to a snake's, preventing a captured fish from backing out and helping to guide the fish down the sabertooth's pharynx. Sabertooth fish are solitary animals; it is not known whether they undergo diel vertical migrations.
Their reproductive habits are poorly studied; they are assumed to be non-guarding, pelagic spawners. True synchronous hermaphroditism with external fertilization is known in Evermannella indica and Odontostomops normalops, and the former species appears to spawn throughout the year. Sabertooth fish larvae are planktonic and have long snouts and oblong eyes before metamorphosis. Both larvae and juveniles remain at shallower depths of 50–100 metres, descending to deeper water with age.