孟
モウ, ボウ, ミョウ, かしら, たけし, たけ, はる, はじめ, つとむ, おさ, はい

chief, beginning

JLPT1 G13 S0 F2127

As per 皿# (cover an object) + 子 child → child energetically throwing off a cover (whether actual or figurative) and making a *beginning*. Also, *eldest sibling* (← energetic growth) → *big/great*. *Mencius/Mengzi* is via an abbreviation of 孟子.

[Full Kanji Etymology List]