Available Definitions:
1) a. - One alone; single; as, the only man present; his only occupation.
2) a. - Alone in its class; by itself; not associated with others of the same class or kind; as, an only child.
3) a. - Hence, figuratively: Alone, by reason of superiority; preeminent; chief.
4) a. - In one manner or degree; for one purpose alone; simply; merely; barely.
5) a. - So and no otherwise; no other than; exclusively; solely; wholly.
6) a. - Singly; without more; as, only-begotten.
7) a. - Above all others; particularly.
8) conj. - Save or except (that); -- an adversative used elliptically with or without that, and properly introducing a single fact or consideration.