WordWeb Online

1. Causing or able to cause nausea
   - nauseating, nauseous, noisome, loathsome, offensive, sickening, vile, loathful [archaic]
    
2. Feeling nausea; feeling about to vomit
   - nauseated, nauseous, sick, sickish
    
3. Causing or fraught with or showing anxiety
   - anxious, nervous, uneasy, unquiet

Derived forms: queasier, queasiest

See also: ill, queasily, queasiness, sick, troubled, unwholesome