The Collaborative International Dictionary of English v.0.48:

Inapposite \In*ap"po*site\, a.
   Not apposite; not fit or suitable; not pertinent. --
   In*ap"po*site*ly, adv.
   [1913 Webster]

WordNet (r) 3.0 (2006):

inapposite
    adj 1: of an inappropriate or misapplied nature [syn:
           inapposite, out of place]

Moby Thesaurus II by Grady Ward, 1.0:

62 Moby Thesaurus words for "inapposite":
   adrift, beside the mark, beside the point, beside the question,
   extraneous, extrinsic, foreign, ill-adapted, ill-assorted,
   ill-chosen, ill-fitted, ill-matched, ill-sorted, ill-suited,
   ill-timed, immaterial, impertinent, improper, inadmissible,
   inapplicable, inappropriate, inapt, incidental, inconsequent,
   inept, infelicitous, irrelative, irrelevant, mal a propos,
   maladjusted, malapropos, misjoined, mismatched, mismated,
   misplaced, nihil ad rem, nonessential, not at issue,
   off the subject, out of character, out of joint, out of keeping,
   out of line, out of place, out of proportion, out of season,
   out of time, out of tune, out-of-the-way, parenthetical, unadapted,
   unapt, unbecoming, unbefitting, unessential, unfit, unfitted,
   unfitting, unqualified, unseasonable, unseemly, unsuitable