What does it mean to be timorous? (From Shakespeare's Othello)

To be timorous is to be frightened.

Roderigo: Here is her father's house. I'll call aloud.
Iago: Do, with like timorous accent and dire yell / As when, by night and negligence, the fire / Is spied in populous cities.
Roderigo: What, ho, Brabantio! Signior Brabantio, ho!
From Shakespeare's Othello; Act 1, Scene 1.