An almond is not a nut but the seed of the almond fruit. Although it is typically called an almond nut, this type belongs to drupes or fruits with outer fleshy parts and pits (1) . . . such as peach and mango.
Reference:(1) Hiskey, Daven. (2010, April 7). Almonds Are Not Nuts. Retrieved from http://www.todayifoundout.com/index.php/2010/04/almonds-are-not-nuts/.