The largehead hairtail (Trichiurus lepturus) fish is a member of the cutlassfish family, Trichiuridae. This fish is a marine carnivorous fish found worldwide in tropical and sub-tropical regions, and is an important fishery resource. The largehead hairtail fish (LHF) has an elongated to compressed body that tapers to a pointed tip. It has a large mouth with barbed fangs on the jaws. In life, the fish is steel blue to silver colored, which makes it very difficult to photograph under water due to reflection from the camera flash. LHF can grow to 2.34 m in length. The large recorded weight is 5 kg and the oldest recorded age is 15 years. They are found at depth of 0 to 589 m with most record between 100 and 350 m. The world annuls catches of LHF were reportedly about 1.3 million ton in 2013. Whereas, in Egypt, cross domestic catch was 1812 tons from the Mediterranean Sea in 2010, and the highest amount of catch per month was 195 tons.

 The flesh of the LHF is firm, get tender when cooked, with a moderate level of "fishiness" to the smell and a low level of oiliness. It is also notable for being fairly easy to debone. It is also considered an excellent source of animal protein, essential amino acids (EAA), polyunsaturated fatty acids (PUFA), vitamins and minerals.