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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- may have been reinforced by Basque, cf. 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).
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.

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.
chita (1), chito (1) (Noun) wooden stake used in quoits, "quoits"

Chita, very early 17th cent; chito 17th cent. Original name of the game quoits. The origin is uncertain and likely from children slang, although a possible cognate in Galician hints the word may have originally meant "wooden stake used to mark real property boundaries."

Romance: Western Vulgar Latin: Galician chito "wooden stake used to mark border boundaries"
chita (2) (Adverb) "quietly"

Derived from chito (2).
chito (2) (Interjection) "quiet!"

Very early 17th cent. From the sound tšššt "shh!," used to impose silence. No further etymology.

Romance: Western Vulgar Latin: Asturian chite, (dialects) chitu