Boyd’s Bible Dictionary:
(large). (1) The harlot of Jericho who received the spies, and married Salmon (Josh. 2:1-21; 6:17-25; Ruth 4:21; Matt. 1:5). (2) Symbolical term for Egypt, implying insolence and violence (like a monster of the sea) (Psa. 87:4; 89:10; Isa. 51:9).
Concise Bible Dictionary:
A poetical name, signifying “insolence,” given to Egypt (Psa. 87:4; Psa. 89:10; Isa. 51:9). The same word occurs in Isaiah 30:7, where the R. V. reads “therefore have I called her Rahab that sitteth still.”
Jackson’s Dictionary of Scripture Proper Names:
arrogance : breadth (the harlot, of Jericho)