Synonyms for Off-the-wall:

• adj.

  •irrational (adjective)
  • disjointed,
  • nutty,
  • unthinking,
  • injudicious,
  • specious,
  • unwise,
  • unsound,
  • wild,
  • insane,
  • demented,
  • wrong,
  • stupid,
  • loony,
  • brainless,
  • foolish,
  • unreasonable,
  • mindless,
  • unstable,
  • kooky,
  • delirious,
  • preposterous,
  • disconnected,
  • sophistic,
  • nonsensical,
  • ridiculous,
  • silly,
  • raving,
  • mad,
  • absurd,
  • incoherent,
  • distraught,
  • fallacious,
  • wacky,
  • aberrant,
  • invalid,
  • crazy.
  •jovial (adjective)
  • amiable,
  • chirpier,
  • cordial,
  • chipper,
  • airy,
  • glad,
  • chirpy,
  • hilarious,
  • jubilant,
  • jollying,
  • pleasant,
  • delightful,
  • humorous,
  • jocose,
  • facetious,
  • bouncy,
  • good-natured,
  • Conversable,
  • blithe,
  • jokey,
  • lighthearted,
  • buoyant,
  • gay,
  • convivial,
  • mirthful,
  • festal,
  • animated,
  • lots of laughs,
  • bantering,
  • companionable,
  • chirpiest,
  • sociable,
  • merry,
  • dizzy,
  • festive,
  • gleeful,
  • Chaffing,
  • jocund,
  • Larking,
  • affable,
  • Daffy,
  • enjoyable,
  • jolly,
  • blithesome,
  • joshing,
  • cheery.
  •odd/oddball (adjective)
  • fantastic,
  • out of the ordinary,
  • freak,
  • uncanny,
  • irregular,
  • character,
  • whimsical,
  • avant-garde,
  • spacey,
  • rare.
  •peculiar (adjective)
  • wonderful,
  • way-out,
  • creepy,
  • oddball,
  • bent,
  • abnormal.
  •quirky (adjective)
  • far out.

• Other synonyms:

  •
  • surreal,
  • idiosyncratic,
  • incongruous,
  • edgy,
  • unreal.
  •Other relevant words:
  • dotty,
  • batty,
  • bananas,
  • off one's rocker,
  • loopy,
  • neurotic,
  • out of place,
  • funky,
  • bonkers,
  • balmy,
  • spacy,
  • novel,
  • out-of-the-way,
  • mentally ill,
  • unorthodox,
  • dippy,
  • out to lunch,
  • capricious,
  • bohemian,
  • rum,
  • funny,
  • touched,
  • far-out,
  • queer,
  • unexpected,
  • extraordinary,
  • Queerish,
  • atypical,
  • weird,
  • maniacal,
  • puzzling,
  • innovative,
  • unrelated,
  • deviant,
  • strange,
  • screwball,
  • unique,
  • mysterious,
  • schizophrenic,
  • lunatic,
  • extraneous,
  • barmy,
  • schizoid,
  • cranky,
  • deranged,
  • potty,
  • offbeat,
  • erratic,
  • alien,
  • irrelevant,
  • bizarro,
  • out of it,
  • outrageous,
  • manic,
  • malapropos,
  • quirky,
  • mystifying,
  • screwy,
  • nuts,
  • gratuitous,
  • exceptional,
  • inapt,
  • kinky,
  • exotic,
  • bugs,
  • unconventional,
  • unconnected,
  • crackers,
  • esoteric,
  • inappropriate,
  • way out,
  • quaint,
  • certifiable,
  • untypical,
  • off-kilter,
  • impertinent,
  • of unsound mind,
  • remarkable,
  • curious,
  • cuckoo,
  • not all there,
  • non compos mentis,
  • odd,
  • psychoneurotic,
  • mental,
  • unusual,
  • unhinged,
  • unprecedented,
  • bughouse,
  • inapplicable,
  • cracked,
  • uncommon,
  • inapposite,
  • twisted,
  • psychotic,
  • goofy,
  • daft,
  • beside the point,
  • berserk,
  • spaced-out,
  • Crack-brained,
  • non-germane,
  • uncalled-for,
  • stark raving mad,
  • loco,
  • singular,
  • nonconcentric,
  • unbalanced,
  • crazed,
  • different,
  • weirdo,
  • schizo,
  • bats,
  • meshuga.

Antonyms for Off-the-wall:

• adj.

  • irrational
    balanced, smart, stable, reasonable, wise, thoughtful, serious, sane, sound, realistic, logical, rational, well, reflective, responsible, sensible.
  • jovial
    gloomy, unfriendly, mean, unpleasant, unsociable, disagreeable, sad, unhappy, heavy-hearted, hateful, depressed, surly.
  • odd/oddball
    conventional, habitual, regular, normal, common, usual, ordinary, standard.
  • peculiar
    Familiar, abnormal, uncharacteristic.
  • Other antonyms:
    average, routine, frequent, customary, expected, garden, unremarkable, wonted, conservative, predictable, prosaic, run-of-the-mill, typical, everyday, unexceptional, workaday, commonplace, conformist.