Worthy or capable of being observed; discernible; noticeable; remarkable.
- Possible to observe: observable phenomena; an observable change in demeanor. See Synonyms at noticeable.
- Deserving or worthy of note; noteworthy: an observable anniversary.
- A physical property, such as weight or temperature, that can be observed or measured directly, as distinguished from a quantity, such as work or entropy, that must be derived from observed quantities.