Timorous (adjective): easily frightened (Merriam-Webster)
Found on Page II, paragraph 4 of The Metamorphosis–>“Once during that long evening, the door on one side of the room was opened very slightly and hurriedly closed again; later on the door on the other side did the same; it seemed that someone needed to enter the room but thought better of it. Gregor went and waited immediately by the door, resolved either to bring the timorous visitor into the room in some way or at least to find out who it was; but the door was opened no more that night and Gregor waited in vain.”
I believe this word in the quote means that Gregor wanted to see the person that kept opening the door slightly and hurriedly. Although he waited all night to come face to face with the person, his wait was to no avail because that unknown person was too frightened to go inside Gregor’s room to witness his horrid condition.
