Source : Webster's Revised Unabridged Dictionary (1913)

Sesquipedal \Ses*quip"e*dal\, Sesquipedalian
\Ses`qui*pe*da"li*an\, a. [Sesqui- + pedal: cf. F.
   sesquip['e]dal, L. sesquipedalis.]
   Measuring or containing a foot and a half; as, a
   sesquipedalian pygmy; -- sometimes humorously applied to long
   words.