"cotton cloth printed with flowers or other colorful patterns," 1719, plural of chint (1610s), from Hindi chint, from Sanskrit chitra-s "clear, bright" (compare cheetah). The plural (the more common form of the word in commercial use) came to be regarded as singular by late 18c., and for unknown reason shifted -s to -z; perhaps after quartz. Disparaging sense, from the commonness of the fabric, is first suggested by 1851 (in George Eliot's use of chintzy).
The term chintz-work is descriptive of that kind of calico-printing which is employed for beds, window-curtains, and other furniture, and it differs more in the richness and variety of the colours, than in any other circumstance. [Abraham Rees, "Cyclopaedia," 1819]
adjective suffix, "full of or characterized by," from Old English -ig, from Proto-Germanic *-iga- (source also of Dutch, Danish, German -ig, Gothic -egs), from PIE -(i)ko-, adjectival suffix, cognate with elements in Greek -ikos, Latin -icus (see -ic). Originally added to nouns in Old English; used from 13c. with verbs, and by 15c. even with other adjectives (for example crispy).
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Harper, D. (n.d.). Etymology of chintzy. Online Etymology Dictionary. Retrieved $(datetime), from https://www.etymonline.com/word/chintzy