adjective, -er, -est, verb, noun | 1. | soft, sweet, and full-flavored from ripeness, as fruit. |
| 2. | well-matured, as wines. |
| 3. | soft and rich, as sound, tones, color, or light. |
| 4. | made gentle and compassionate by age or maturity; softened. |
| 5. | friable or loamy, as soil. |
| 6. | mildly and pleasantly intoxicated or high. |
| 7. | pleasantly agreeable; free from tension, discord, etc.: a mellow neighborhood. |
| 8. | affably relaxed; easygoing; genial: a mellow teacher who is very popular with her students. |
| 9. | to make or become mellow. |
| 10. | Slang. a state, atmosphere, or mood of ease and gentle relaxation. |
| 11. | mellow out, Slang.
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mellow
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mellow out
Become genial or pleasant, calm down, relax, as in The teacher mellowed out when they explained what had happened. This expression uses mellow in the sense of "ripening," with the connotation of softness and sweetness. [Slang; late 1900s]