Ruins. (1.) One of the royal cities of the Canaanites (Josh. "10:1; Gen. 12:8; 13:3). It was the scene of Joshua's defeat, and" afterwards of his victory. It was the second Canaanite city taken by Israel (Josh. 7:2-5; 8:1-29). It lay rebuilt and inhibited by the Benjamites (Ezra 2:28; Neh. 7:32; 11:31). It "lay to the east of Bethel, "beside Beth-aven." The spot which is" "most probably the site of this ancient city is Haiyan, 2 miles" "east from Bethel. It lay up the Wady Suweinit, a steep, rugged" "valley, extending from the Jordan valley to Bethel." "(2.) A city in the Ammonite territory (Jer. 49:3). Some have thought that the proper reading of the word is Ar (Isa. 15:1).

"Hind of the dawn, a name found in the title of Ps. 22. It is" probably the name of some song or tune to the measure of which "the psalm was to be chanted. Some, however, understand by the" "name some instrument of music, or an allegorical allusion to the" subject of the psalm.

"The atmosphere, as opposed to the higher regions of the sky (1" Thess. 4:17; Rev. 9:2; 16:17). This word occurs once as the rendering of the Hebrew ruah (Job 41:16); elsewhere it is the "rendering of shamaiyim, usually translated "heavens." "The expression "to speak into the air" (1 Cor. 14:9) is a "proverb denoting to speak in vain, as to "beat the air" (1 Cor." 9:26) denotes to labour in vain.

See where Ai occurs in the Bible...

Definition of Ai:
"or Hai, mass; heap"