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

-ish \-ish\ as. -isc; akin to g. -isch, ohg. -isc, goth.  dan.
   -isk, gr. ?. cf. -esque.
   a suffix used to from adjectives from nouns and from
   adjectives. it denotes relation, resemblance, similarity, and
   sometimes has a diminutive force; as, selfish, boyish,
   brutish; whitish, somewhat white.
   1913 webster
see also:
-esque 

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

-ish \-ish\ oe. -issen, fr. f. -is, -iss- found in the present
   particle, etc., of certain verbs, as finir to finish, fleurir
   to flourish, corresponding to l. -escere, an inchoative
   ending.
   a verb ending, originally appearing in certain verbs of
   french origin; as, abolish, cherish, finish, furnish,
   garnish, impoverish.
   1913 webster

[3] : Virtual Entity of Relevant Acronyms (Version 1.9, June 2002)

ish
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-Ish >> I Words
-Ish, definition of term: -Ish
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