also: むにむざん
noun, noun which may take the genitive case particle 'no'
with all one's might; single-mindedly; headlong
Describes doing something with intense concentration and determination, often rushing into it without distraction. Common in set phrases like 無二無三に～する.
彼は無二無三に仕事に打ち込んだ。
He threw himself into his work single-mindedly.
無二無三の努力が実を結んだ。
His intense, single-minded effort paid off.
noun, noun which may take the genitive case particle 'no'
one and only; unique; unparalleled
Rare, somewhat archaic sense meaning something is the only one of its kind. More commonly expressed with 唯一無二 or 無二 today.
この作品は無二無三の傑作だ。
This work is a unique masterpiece.
Also means 'single-minded' or 'with complete concentration', but 無二無三 carries a nuance of rushing headlong into something.
Standard kanji spelling for this yojijukugo. The reading むにむざん is also possible but less common.
Alternate reading; むにむさん is more common.
Derived from the Buddhist expression 無二亦無三, “there is neither a second nor a third,” found in the Lotus Sutra. Its sense developed from uniqueness or exclusivity to single-minded, headlong action.