This is the 42nd most frequent Armenian word.
երբ
"երբ" means "when" in English.
The word 'երբ' is used as a temporal conjunction to introduce a subordinate clause specifying a time.
Երբ դու կգաս, մենք ընթրիք կսպասենք։
When you arrive, we will wait for dinner.
Here, 'երբ' is used as a relative conjunction referring to a time in the past.
Պատմիր ինձ այն մասին, երբ դու առաջին անգամ տեսար ծովը։
Tell me about the time when you saw the sea for the first time.
In this question, 'երբ' functions as an interrogative adverb asking about time.