By "sensible" Berkeley means "able to be sensed." Those things we can see, hear, feel, smell, or taste are sensible things.
("Sensible" as used by Berkeley is not a synonym of "reasonable," as it may be for modern English speakers.)
First definition of sensible things: "those things that can be perceived by the senses." (P 163a)
Revised definition of sensible things: "those [things] which are immediately perceived by sense." (P 163b)