Wordnet 3.0
NOUN (1)
1. 
 fanciful but graceful asymmetric ornamentation in art and architecture that originated in France in the 18th century; 
ADJECTIVE (1)
1. 
 having excessive asymmetrical ornamentation; 
- Example: "an exquisite gilded rococo mirror"
The Collaborative International Dictionary of English v.0.48:
Rococo \Ro*co"co\, n. [F.; of uncertain etymology.]
   A florid style of ornamentation which prevailed in Europe in
   the latter part of the eighteenth century.
   [1913 Webster]
The Collaborative International Dictionary of English v.0.48:
Rococo \Ro*co"co\, a.
   Of or pertaining to the style called rococo; like rococo;
   florid; fantastic.
   [1913 Webster]
WordNet (r) 3.0 (2006):
rococo
    adj 1: having excessive asymmetrical ornamentation; "an
           exquisite gilded rococo mirror"
    n 1: fanciful but graceful asymmetric ornamentation in art and
         architecture that originated in France in the 18th century
Moby Thesaurus II by Grady Ward, 1.0:
80 Moby Thesaurus words for "rococo":
   Gothic, arabesque, archaic, baroque, baroqueness, bizarre,
   brain-born, busy, bygone, chichi, chinoiserie, dated, deformed,
   dream-built, elaborate, elaborateness, elegance, elegant,
   extravagant, fanciful, fanciness, fancy, fancy-born, fancy-built,
   fancy-woven, fantasque, fantastic, fine, fineness, flamboyance,
   flamboyant, florid, floridity, floridness, floweriness, flowery,
   freak, freakish, frilly, fussy, grotesque, high-wrought, labored,
   luxuriance, luxuriant, luxurious, luxuriousness, maggoty,
   malformed, misbegotten, misshapen, moldy, monstrous, moresque,
   moth-eaten, notional, old hat, ornate, ostentation, ostentatious,
   outdated, outlandish, overelaborate, overelaborateness,
   overelegance, overelegant, overlabored, overornamentation,
   overworked, overwrought, passe, picturesque, preposterous,
   pretty-pretty, rich, richness, teratogenic, teratoid, whimsical,
   wild
The Jargon File (version 4.4.7, 29 Dec 2003):
rococo
 adj.
    Terminally baroque. Used to imply that a program has become so encrusted
    with the software equivalent of gold leaf and curlicues that they have
    completely swamped the underlying design. Called after the later and more
    extreme forms of Baroque architecture and decoration prevalent during the
    mid-1700s in Europe. Alan Perlis said: ?Every program eventually becomes
    rococo, and then rubble.? Compare critical mass.
The Free On-line Dictionary of Computing (30 December 2018):
rococo
    Baroque in the extreme.  Used to imply that
   a program has become so encrusted with the software equivalent
   of gold leaf and curlicues that they have completely swamped
   the underlying design.  Called after the later and more
   extreme forms of Baroque architecture and decoration prevalent
   during the mid-1700s in Europe.  Alan Perlis said: "Every
   program eventually becomes rococo, and then rubble."
   Compare critical mass.
   [Jargon File]
   (1996-04-06)