Search Result for "impermissibly": 
Wordnet 3.0

ADVERB (1)

1. not permissibly;
- Example: "the radon level in the basement was impermissibly high"



WordNet (r) 3.0 (2006):

impermissibly
    adv 1: not permissibly; "the radon level in the basement was
           impermissibly high" [ant: allowably, permissibly]