にない

not in; no other; unlikely to

→ に
phrase Common #3,995
not in; no other; unlikely to Its meaning depends on the expression before it. In a location phrase, it means “not in” or “not at” (e.g. 銃器はタソケ地区にない, “There are no firearms in the Tasoke district”). In 他にない, it means “there is no other.” In そうにない, it means “unlikely to.”
JA: それはありそうにないな。
EN: That doesn't seem likely.

まだ病気だということを考えると彼は今日来そうにない

Considering that he’s still sick, he probably won’t come today.

彼は今までにないほど勤勉だ

He is more hardworking than ever.

彼が一番やってきそうにない

He's the last person I'd expect to do it.

なぜ記録にない

Why isn't it in the records?

— ア・フュー・グッドメン (1992)

彼は重病回復しそうにない

He is seriously ill and doesn't seem likely to recover.

銃器タソケ地区にない

There are no firearms in the Tasoke district.

— エリート・スクワッド ブラジル特殊部隊BOPE (2010)

彼女は来そうにない

She doesn’t look like she’s coming.

今年の夏は例年にない暑さ

This summer is unusually hot.