sober (Adjective) — Not affected by a chemical substance (especially alcohol).
sober (Adjective) — Dignified and sombre in manner or character and committed to keeping promises. ex. "as sober as a judge"
sober (Adjective) — Lacking brightness or colour; dull. ex. "sober Puritan grey"
sober (Adjective) — Completely lacking in playfulness.
sober (Verb) — Cause to become sober. ex. "A sobering thought"
sober (Verb) — Become more realistic. ex. "After thinking about the potential consequences of his plan, he sobered up"
sober (Verb) — Become sober after excessive alcohol consumption. ex. "Keep him in bed until he sobers up"