A polite greeting used to welcome customers in shops, restaurants, etc.; similar to 'welcome' but primarily for customer service contexts.
店員:「いらっしゃいませ。本日は何をお探しですか？」
Clerk: "Welcome. What are you looking for today?"
レストランに入ると、全員で『いらっしゃいませ！』と声を揃えた。
When we entered the restaurant, everyone greeted us in unison with 'Welcome!'.
小さな店でも、出迎えるときは必ずいらっしゃいませと言う。
Even small shops always say 'welcome' when greeting customers.