Gellir diffinio trawma mawr fel anafiadau lluosog a difrifol sy’n arwain at anabledd neu farwolaeth. Gallant gynnwys anafiadau difrifol i’r pen, anafiadau lluosog a achosir gan ddamweiniau traffig ar y ffyrdd, damweiniau diwydiannol, cwympiadau, digwyddiadau damweiniau torfol, ac anafiadau cyllyll a gynnau. Trawma mawr yw’r prif achos o farwolaethau ymhlith pobl o dan 45 oed, a hefyd yn achos sylweddol o salwch neu iechyd gwael tymor byr a hirdymor.
Major trauma can be defined as multiple and serious injuries resulting in disability or death. These may include serious head injuries, multiple injuries caused by road traffic accidents, industrial accidents, falls, mass casualty events, and knife and gunshot wounds. It is the leading cause of death in people under the age of 45 and a significant cause of short and long-term illness or poor health.