ちびる

/tubu/ → /t͡subu/ → /t͡ɕibu/ → (grammatical shift) /t͡ɕibiru/

Shift from earlier form 禿ぶ (tsubu, “to become round and small, such as from wear; to become bald”). Cognate with 粒 (tsubu, “grain; small thing”), 円ら (tsubura, “round and plump; small and round”).[1]

• (Tokyo) ちび​る [chìbíꜜrù] (Nakadaka – [2])[2][3]
• (Tokyo) ちびる [chìbírú] (Heiban – [0])[2][3]
• IPA^(key): [t͡ɕibʲiɾɯ̟ᵝ]

ちびる • (chibiru) intransitive ichidan (stem ちび (chibi), past ちびた (chibita))

1. to wear down and become small

• 禿(ち)び筆(ふで) (chibifude, “a worn-down calligraphy brush”)
• 禿(ちび)る (chibiru, “to wear down and become small”, 四段活用 (yodan katsuyō, “quadrigrade conjugation”), rare)
• ちび (chibi, “runt, pipsqueak”)

Possibly derived from the underlying sense of little bit, small amount of noun 粒 (tsubu, root of homophonous verb 禿びる (“to wear down”)), or a shift in sense from that verb.

First attested in a work from 1772.[4]

• (Tokyo) ちび​る [chìbíꜜrù] (Nakadaka – [2])[2]
• IPA^(key): [t͡ɕibʲiɾɯ̟ᵝ]

ちびる • (chibiru) godan (stem ちびり (chibiri), past ちびった (chibitta))

1. [from before 1772] (informal) to stint, to pay out or use something in a stingy fashion

   Synonyms: 出し惜しむ (dashioshimu), けちけちする (kechikechi suru)

2. [from 1772] (informal) to leak something out a little bit at a time; (by extension) to urinate or defecate a small amount
3. [from early 1890s] (informal) to drink a little bit at a time, to sip slowly, to nurse one's drink