The goblin shark has a distinctively long and flat snout, resembling a sword blade. The proportional length of the snout decreases with age. The eyes are small and lack protective nictitating membranes; behind the eyes are spiracles. The large mouth is parabolic in shape. The jaws are very protrusible and can be extended almost to the end of the snout, though normally they are held flush against the underside of the head. It has 35–53 upper and 31–62 lower tooth rows. The teeth in the main part of the jaws are long and narrow, particularly those near the symphysis (jaw midpoint), and are finely grooved lengthwise. The rear teeth near the corners of the jaw are small and have a flattened shape for crushing. Much individual variation of tooth length and width occurs, as for whether the teeth have a smaller cusplet on each side of the main cusp, and regarding the presence of toothless gaps at the symphysis or between the main and rear teeth. The five pairs of gill slits are short, with the gill filaments inside partly exposed; the fifth pair is above the origin of the pectoral fins.