人 as a suffix. General rule for a reading?

Question

When 人 is used as a suffix the reading could be jin or nin (or other readings?).

犯人 - はんにん

別人 - べつじん

Is there a general rule to tell when the reading will be jin vs nin, or should I just learn it case by case?

Answer 1

Both ジン and ニン are 音読み of the character 人. ジン is the 漢読み and ニン is the 呉読み (See http://dictionary.goo.ne.jp/jn/113338/meaning/m0u/).

Unfortunately, there's no easy way to know which reading to use for all cases since it depends on when the word was imported from China or alternately invented in Japan.

There's also a set of 訓読み to be aware of : ひと、びと、 and うと in compound words. And completely irregular readings like [大人]{おとな}　-- interestingly there's also a [大人]{ダイジン} reading which is less frequent.

One thing I can suggest is that nationalities are all ジン : [中国人]{チュウゴクジン}, [フランス人]{フランスジン}, など

Answer 2

No rule, just case by case.

There are also words like this:

• 素人{しろうと}
• 玄人{くろうと}
• 狩人{かりゅうど}
• 助{すけ}っ人{と}