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

lengthy \length"y\ -y^, a. compar. lengthier
   -i^~er; superl. lengthiest.
   having length; rather long or too long; prolix; not brief; --
   said chiefly of discourses, writings, and the like. "lengthy
   periods." --washington. "some lengthy additions." --byron.
   "these would be details too lengthy." --jefferson. "to cut
   short lengthy explanations." --trench.
   1913 webster lenience
see also:
lengthier lengthiest 

[2] : WordNet (r) 2.0

lengthy
     adj : relatively long in duration; tediously protracted; "a
           drawn-out argument"; "an extended discussion"; "a
           lengthy visit from her mother-in-law"; "a prolonged and
           bitter struggle"; "protracted negotiations" syn: drawn-out,
            extended, prolonged, protracted
     also: lengthiest, lengthier
see also:
drawn-out extended prolonged protracted lengthiest lengthier 

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

53 moby thesaurus words for "lengthy":
   a mile long, boring, colossal, de longue haleine, dragging,
   drawn-out, dull, elongate, elongated, endless, extended, extensive,
   far-flung, far-reaching, fargoing, filled out, gangling, gangly,
   garrulous, giant, gigantic, interminable, lank, lanky, leggy, long,
   long-drawn-out, long-legged, long-spun, long-winded, longiloquent,
   longish, longsome, loquacious, no end of, overlong, padded, prolix,
   prolonged, protracted, rangy, sesquipedal, sesquipedalian,
   spun-out, statuesque, talkative, tall, tedious, unrelenting,
   verbose, windy, without end, wordy

Lengthy >> L Words
Lengthy, definition of term: Lengthy
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