The term 'Adieu in Latin' can be expressed in two ways: 'ALOHA' (5 letters) and 'AVE' (3 letters). 'ALOHA' is a Hawaiian word that is used to express both hello and goodbye. It is derived from the Proto-Polynesian word 'alofa', which means love, affection, peace, compassion, and mercy. 'AVE' is a Latin word that is used to express farewell. It is derived from the Latin verb 'avere', which means 'to be well'. Both words are used to express a fond farewell.