彼は何物にも代えがたい存在だ。
He is irreplaceable (lit. something that cannot be exchanged for anything).
anything (else); nothing (but)
Used in negative or limiting constructions such as 何物にも, 何物でもない, meaning 'nothing but' or 'anything else'. Often emphasizes exclusivity or negation.
He is unfazed by anything.
That is nothing (of significance).
Standard kanji spelling; high priority in news and frequency lists.
Alternate spelling using kana for もの; sometimes used for clarity or emphasis.
Compound of 何 (nani, 'what') + 物 (mono, 'thing'). The reading なにもの is a straightforward combination of the two components.