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chico (Adjective, Noun) "small;" (masc.) "boy," "child;" (fem.) "girl"

12th cent. Perhaps from Latin ciccus "nothing," earlier "something worthless," but originally "the thin membrane surrounding the grains of a pomegranate." Presumably borrowed from an unattested Ancient Greek word *κίκκος (kíkkos) "shell of a pomegranate," hypothesized by Beekes (2008) on the basis of the Latin word and possible Greek derivatives κίκκαβος (kíkkabos) "small coin in the Underworld," κικκάβι(ο)ν (kikkábi(o)n) "nothing," and κικαῖος (kikaîos), a word of obscure meaning. Ultimately of unknown origin.

Also the origin of the surname Chico.

Romance: Western Vulgar Latin: Asturian chico, Aragonese chicot, Catalan xic, French chiquet, Italian cica

The sense of "small" was first and then was extended to children. The change from c- to may be due to Basque influence, via txiki "small," "few," from earlier tiki. Also note 18th cent. colloquialism chicho "small child (who has begun to speak)," from *cic(c)us via double-palatalization distortion found in children's speech (compare niño and ñoño).

Chico para todo "trustworthy domestic worker."

Chico con grande "everything." Compare English both large and small.
china (1) f. (Noun) "pebble;" "doubt"

Very late 15th cent. The meaning of doubt is a poetic metaphor. Of unknown origin, presumably from a pre-form *cina. Perhaps a back formation in Vulgar Latin from Latin cinnabris "red mercuric sulfide," but the semantics are obscure and do little to help the theory.

Chin is an apocopated form.

Romance: Western Vulgar Latin: Asturian china, Portuguese china, Galician china
China (2) f. (Noun) "China"

Borrowed from Persian čini "Chinese." Probably from the name of the Qín dynasty.
china (3) f. (Noun) (slang) "money"

From Basque txin "coins," "clink." An onomatopoeia from the sound of coins clinking together.
china (4) f. (Noun) "indigenous American woman," "mixed-raced woman"

16th cent. From Quechua china "female animal," "servant."
chingar (Verb) (obscene) "to fuck;" (Latin America) "to fail," "to miscarry"

19th cent. From Romany chingarár "to fight." Corominas (1991) is skeptical the Latin American senses of failure derive from the same Romany word, and instead speculates a source in an unknown New World language or languages. Chingar is probably from Proto-Indo-European *gwhen- "to strike" but the exact route is uncertain.