The story
From Aamir, the name of the son of the inventor of the game (Omar Syed), spelled backwards, plus an initial a.
Etymology from Wiktionary, CC BY-SA 4.0.
Arimaa
Today it means: A board game for two players, each beginning with sixteen pieces moving according to fixed rules across an 8×8 board with the objective to get one rabbit to the opposite side, kill all the opponents rabbits on your turn, or make the opponent have no legal moves on their turn. Full definition →