The Collaborative International Dictionary of English v.0.48:

legalese \legalese\ n.
   A style of writing or speaking heavily emphasizing the
   abstruse technical vocabulary of the law, to the point where
   a speech or document may be incomprehensible to
   non-specialists.
   [WordNet 1.5]

WordNet (r) 3.0 (2006):

legalese
    n 1: a style that uses the abstruse technical vocabulary of the
         law

The Jargon File (version 4.4.7, 29 Dec 2003):

legalese
 n.

    Dense, pedantic verbiage in a language description, product specification,
    or interface standard; text that seems designed to obfuscate and requires a
    language lawyer to parse it. Though hackers are not afraid of high
    information density and complexity in language (indeed, they rather enjoy
    both), they share a deep and abiding loathing for legalese; they associate
    it with deception, suits, and situations in which hackers generally get
    the short end of the stick.


The Free On-line Dictionary of Computing (30 December 2018):

legalese

   Dense, pedantic verbiage in a language description, product
   specification, or interface standard; text that seems designed
   to obfuscate and requires a language lawyer to parse it.
   Though hackers are not afraid of high information density and
   complexity in language (indeed, they rather enjoy both), they
   share a deep and abiding loathing for legalese; they associate
   it with deception, suits, and situations in which hackers
   generally get the short end of the stick.