grotesque

from The American Heritage® Dictionary of the English Language, 5th Edition.

• adjective Characterized by ludicrous, repulsive, or incongruous distortion, as of appearance or manner. synonym: ugly.
• adjective Outlandish or bizarre, as in character or appearance. synonym: fantastic.
• adjective Of, relating to, or being the grotesque style in art or a work executed in this style.
• noun One that is grotesque.
• noun A style of painting, sculpture, and ornamentation in which natural forms and monstrous figures are intertwined in bizarre or fanciful combinations.
• noun A work of art executed in this style.

from The Century Dictionary.

• Consisting of or resembling artificial grotto-work.
• Hence Of the fantastic character of such grotto-work and of its decoration; wildly formed; of irregular forms and proportions; ludicrous; antic (which see), as the arabesques of the Renaissance, in which figures human to the waist terminate in scrolls, leafage, and the like, and are associated with animal forms and impossible flowers; hence, in general, whimsical, extravagant, or odd; absurdly bold: often, or more commonly, used in a sense of condemnation or depreciation.
• Synonyms Fantastic, etc. (see fanciful); whimsical, wild, strange.
• noun That which is grotesque, as an uncouth or ill-proportioned figure, rude and savage scenery, an inartistic, clownish, or absurd fancy, a clumsy satire, or the like.
• noun Specifically In art, a capricious figure, work, or ornament; especially, a variety of arabesque which as a whole has no type in nature, being a combination of the parts of animals and plants, and of other incongruous elements.
• noun In printing, any uncouth form of type; specifically, in Great Britain, the black square-cut display-type called gothic in the United States.

from the GNU version of the Collaborative International Dictionary of English.

• adjective Like the figures found in ancient grottoes; grottolike.
• adjective Wildly or strangely formed; whimsical; extravagant; of irregular forms and proportions; fantastic; ludicrous; antic.
• noun A whimsical figure, or scene, such as is found in old crypts and grottoes.
• noun Artificial grotto-work.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• adjective distorted and unnatural in shape or size; abnormal and hideous
• adjective disgusting or otherwise viscerally reviling.
• adjective typography sans serif.
• noun A style of ornamentation characterized by fanciful combinations of intertwined forms.
• noun Anything grotesque.
• noun typography A sans serif typeface.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• adjective ludicrously odd
• adjective distorted and unnatural in shape or size; abnormal and hideous
• noun art characterized by an incongruous mixture of parts of humans and animals interwoven with plants