[1] : The Collaborative International Dictionary of English v.0.48

offhand \off"hand`\, a.
   instant; unprepared; ready; extemporaneous; unrehearsed; as,
   an offhand speech; offhand excuses; an offhand comment. --
   adv. in an offhand manner; as, he replied offhand.
   1913 webster

[2] : WordNet (r) 2.0

offhand
     adj 1: with little or no preparation or forethought; "his ad-lib
            comments showed poor judgment"; "an extemporaneous
            piano recital"; "an extemporary lecture"; "an
            extempore skit"; "an impromptu speech"; "offhand
            excuses"; "trying to sound offhanded and reassuring";
            "an off-the-cuff toast"; "a few unrehearsed comments"
            syn: ad-lib, extemporaneous, extemporary, extempore,
             impromptu, offhanded, off-the-cuff, unrehearsed
     2: casually thoughtless or inconsiderate; "an offhand manner";
        "she treated most men with offhand contempt" syn: offhanded
     adv 1: without previous thought or preparation; "couldn't give the
            figures offhand"; "we decided offhand to go to
            canada"; "she had made these remarks offhandedly"
            syn: offhanded, offhandedly
     2: in a casually inconsiderate manner; "replied offhand, his
        mind a million miles away"; "she threw him over
        offhandedly without even a dear-john letter" syn: offhanded,
         offhandedly
see also:
ad-lib extemporaneous extemporary extempore impromptu offhanded 
off-the-cuff unrehearsed offhandedly 

[3] : WordNet (r) 2.0

off-hand
     adv : without preparation; "i don't know the figures off-hand"
           syn: ex tempore
see also:
ex tempore 

[4] : Moby Thesaurus II by Grady Ward, 1.0

161 moby thesaurus words for "offhand":
   bohemian, abrupt, ad lib, ad libitum, ad-lib, affable, airily,
   airy, aloof, any old way, any which way, anyhow, at short notice,
   at sight, blase, brusque, bunglingly, by ear, by the by,
   by the way, careless, carelessly, casual, casually, cavalier,
   clumsily, cool, cordial, cursorily, cursory, curt, degage,
   devil-may-care, disregardant, disregardful, disregardfully,
   distant, easy, easygoing, en famille, en passant, extemporaneous,
   extemporaneously, extemporarily, extemporary, extempore, familiar,
   familiarly, flippant, folksy, forgetful, forgetfully,
   free and easy, glib, gracious, haphazardly, haymish, heedless,
   heedlessly, helter-skelter, hit and miss, hit or miss, homely,
   homey, impromptu, improvisatorial, improvise, improvised,
   improviso, in passing, inattentively, incidentally, inconsiderate,
   inconsiderately, indifferent, informal, informally, insouciant,
   irregular, jury-rigged, lackadaisical, lazy, light-hearted, loose,
   makeshift, messily, natural, naturally, nonchalant, oblivious,
   off the cuff, off the hip, off-the-cuff, offhanded, offhandedly,
   on sight, once over lightly, out of hand, parenthetically,
   perfunctorily, perfunctory, plain, plainly, promiscuously,
   reckless, recklessly, regardless, regardlessly, relaxed, relaxedly,
   respectless, sans ceremonie, simple, simply, slapdash, sloppily,
   smooth, sociable, spur-of-the-moment, stopgap, superficial,
   superficially, tactless, tactlessly, thoughtless, thoughtlessly,
   unaffected, unaffectedly, unassuming, unassumingly, unceremonious,
   unceremoniously, unconcerned, unconstrained, unconstrainedly,
   unconventional, undiplomatic, ungracious, unguardedly, unheedful,
   unheedfully, unheeding, unheedingly, uninterested, unmindful,
   unmindfully, unofficial, unofficially, unpremeditated, unprepared,
   unready, unrehearsed, unsolicitous, unsolicitously, unstudied,
   untactful, unthinking, unthinkingly, unvigilantly, unwarily,
   without ceremony

Offhand >> O Words
Offhand, definition of term: Offhand
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