太郎

Appears to be a coinage within Japanese from Middle Chinese-derived elements, as a compound of 太 (ta, “fat; great”) +‎ 郎 (rō, “boy”).

Initially used as a given name for an eldest son.[1]

Attested since at least the early 900s.[1]

• (Tokyo) た​ろー [táꜜròò] (Atamadaka – [1])[2][3]
• IPA^(key): [ta̠ɾo̞ː]

太(た)郎(ろう) • (Tarō) ^{←たらう (tarau)?}

1. [from at least the early 900s] a male given name (particularly for an eldest son)
2. [from late 1100s] (euphemistic, by extension) the first, the biggest, the tallest, the most, the best

Used as a generic or stereotypical male name, like English Joe.

The first, biggest, etc. sense is used as if it were a name. This is often found used in combinations as a kind of euphemism, such as referring to the 利根川 (Tone-gawa, “Tone River”) as 坂東太郎 (Bandō Tarō, literally “Tarō of the Bandō region”), essentially describing the Tone River as the "eldest son" (i.e. foremost, biggest) of the rivers in the Bandō region.

太(た)郎(ろう) • (tarō) ^{←たらう (tarau)?}

1. (Internet slang) generic protagonist of isekai-kei and social-network games
2. [from 1797] (derogatory, slang) a fool, an idiot
3. [from 1929] (derogatory, slang, criminal jargon) a country bumpkin, a mark (as a targeted victim for theft or other crime)

太(た)郎(ろう) • (-tarō) ^{←たらう (tarau)?}

1. suffixing element in male given names

   健(けん)太郎(たろう)、慎(しん)太郎(たろう)、陽(よう)太郎(たろう)、小(こう)太郎(たろう)

   Kentarō, Shintarō, Yōtarō, Kōtarō

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