N1 Comparison and Contrast

~ならいざしらず: meaning, usage and examples

~ならいざしらず means: if it were... (it'd be different), but...

Updated 9 November 2026 · By the My Senpai team · Spotted a mistake? Tell us

Examples

1. 子供こどもならいざしらず、大人おとながそんなことをしてはダメだ。

   If it were a child, it'd be different, but an adult shouldn't do such a thing.

2. 10分じゅっぷんや20分ぷんの遅刻ちこくならいざしらず、1時間じかんも待またせるなんて。

   Being 10 or 20 minutes late is one thing, but making someone wait a whole hour...

3. 素人しろうとならいざしらず、プロがこんな初歩しょほ的てきな間違まちがいをするとは。

   An amateur, maybe, but for a professional to make such a basic mistake...

4. 昔むかしならいざしらず、今いまはスマホで何なにでも調しらべられる。

   That may have been true in the old days, but now you can look up anything on a smartphone.

When to use it

Sets aside one case as understandable or exceptional, then says the actual case is different and not acceptable. It works like "X would be one thing, but Y..." and the second clause usually carries criticism or surprise. Example: 子供こどもならいざしらず、大人おとながそんなことをしてはいけない (a child, maybe, but an adult should not do that).

Nuance

Formal to semi-formal, used in speech and writing. The tone is critical, often indignant. The first part is an easy or extreme case (a child, the old days, a beginner); the second part is the real situation that falls short. The second clause is often left unfinished with とは or なんて.

Compare

ならともかく has the same structure and is more everyday: 子供こどもならともかく、大人おとなが…. ならいざしらず sounds more formal and more critical. はさておき only postpones a topic without contrasting cases: 冗談じょうだんはさておき、本題ほんだいに入はいろう (joking aside, let us get to the point).

Tip: いざしらず literally means "I do not know about that." Read it as "X I could understand, but Y?" and expect a complaint to follow.