WordWeb Online

1. Serving no useful purpose; having no excuse for being
   "otiose lines in a play";
   - pointless, purposeless, senseless, superfluous, wasted
    
2. Producing no result or effect
   "an otiose undertaking";
   - futile, ineffectual, unavailing, meaningless
    
3. Disinclined to work or exertion
   "otiose kings under whose rule the country languished";
   - fainéant [archaic], indolent, lazy, slothful, work-shy

See also: idle, useless, worthless