Possible Definitions:
1. Rare (a.) Early.
2. Rare (superl.) Nearly raw; partially cooked; not thoroughly cooked; underdone; as, rare beef or mutton.
3. Rare (superl.) Not frequent; seldom met with or occurring; unusual; as, a rare event.
4. Rare (superl.) Of an uncommon nature; unusually excellent; valuable to a degree seldom found.
5. Rare (superl.) Thinly scattered; dispersed.
6. Rare (superl.) Characterized by wide separation of parts; of loose texture; not thick or dense; thin; as, a rare atmosphere at high elevations.