slang - What is the meaning of the phrase いい年こいて?

いい年こいて

I understand that toshi means age in this context, but what is a good example of using this in a sentence (informal). What is いい年 in this context?

Answer

Here are some facts about いい年:

• Another way of saying いい年 is いい大人　(a good adult).


• いい年こいて is the informal version of いい年して.

That being said いい年 literally translates to "a good age" which a another way of saying adult or even responsible adult.

いい年こいて can be used in a sentence as follows (Fill the blank with what the person shouldn't be doing):

Whats a good/responsible adult doing ________!?

Ex: いい年こいて薬やってんじゃんえよ！(what's a responsible adult doing drugs for?)