Using the word น่า naa3 in Thai before a word is similar to adding ‘–worthy’ to the end of a word in English. This, in most but not all cases, adds a positive implication that the item of interest is worth doing or worth having that feeling for it. It should only be added to verbs and adjectives.
The word น่า, means ‘should’ or ‘worthy of’.
น่ากลัว naa3 glua2 scary
น่ากิน naa3 gin1 worth eating
น่าอ่าน naa3 aan2 worth reading
ไม่น่าอ่าน mai3 naa3 aan2 not worth reading
ไม่น่าเชื่อ mai3 naa3 cheu3 not worth believing; not believable; unbelievable!
น่าสงสาร naa3 song2saan5 pathetic; worth having empathy for
น่ารู้ naa3 ruu4 worth knowing; knowledge worth having
ไม่น่ารู้ mai3 naa3 ruu4 not worth knowing; knowledge not worth having
น่าเกลียด naa3 glead2 ugly (note that this has a negative – not positive – implication)
ไม่น่าเกลียด mai3 naa3 glead2 not ugly (but not necessarily pretty!)
น่ากอด naa3 gawd2 worth hugging; huggable
น่าจะไป naa3 ja2 bpai1 it’s worth going to/traveling to
น่าขำ naa3 kum5 it’s funny, it’s hilarious
ไม่น่าขำ mai3 naa3 kum5 it’s not funny
น่าดู naa3 duu1 worth seeing (like a TV show, or a travel attraction)
There are two Thai words that are similar but can be a little confusing. Directly translated, naa3 rak4 น่ารัก would mean ‘loveable’. But it really means ‘cute’ (like your girlfriend). It should not be confused with naa3 en1duu1 น่าเอ็นดู, which is the kind of ‘cute’ your little dog is.
น่ารัก naa3 rak4 cute (for your girlfriend, or a stuffed Pikachu doll)
น่าเอ็นดู naa3 en1duu1 cute (for a little dog, or a baby)
note: There is another word in Thai, หน้า naa3, which has the exact same pronunciation but different spelling. It has several other meanings and should not be confused with น่า.