1. [n]  a place where arms are manufactured
2. [n]  a military structure where arms and ammunition and other military equipment are stored and training is given in the use of arms
3. [n]  all the weapons and equipment that a country has
4. [n]  a collection of resources; "he dipped into his intellectual armory to find an answer"

ARMOURY is a 7 letter word that starts with A.

the place in which armour was deposited when not used (Neh. 3:19; Jer. 50:25). At first each man of the Hebrews had his own arms, because all went to war. There were no arsenals or magazines for arms till the time of David, who had a large collection of arms, which he consecrated to the Lord in his tabernacle (1 Sa,. 21:9; 2 Sam. 8:7-12; 1 Chr. 26:26, 27).