nauk

1. lesson; moral
   Neka ti ovo bude nauk za ubuduće. — Let this be a lesson to you.
   Kakav je nauk ove priče? — What's the moral of this story?
2. formal teaching; doctrine
   Hrišćanski nauk govori o ljubavi prema bližnjem. — Christian teaching speaks of love for one's neighbour.

Do not confuse with nauka, 'science'.