ようこそ

よ

う

こ

そ

Common wordJLPTN1Freq.FrequencyTop 10,000

Meanings

1

A warm greeting used when welcoming someone to a place, event, or group. Often used in set phrases like ようこそ日本へ (Welcome to Japan).

ようこそお越こしくださいました。

Thank you for coming; welcome.

ようこそ〈場ば所しょ〉へwelcome to 〈place〉
ようこそ日本にほんへいらっしゃいました。
Welcome to Japan.
ようこそ〈場ば所しょ〉へおいでくださいましたa polite way to say welcome to 〈place〉, thanking someone for coming
ようこそ弊へい社しゃへおいでくださいました。
Welcome to our company; thank you for coming.

いらっしゃいN4
いらっしゃい is a casual welcome used mainly in shops or at the door, while ようこそ is more formal and common in speeches or written greetings.
いらっしゃいませN5
いらっしゃいませ is the fixed greeting shop staff say to entering customers, whereas ようこそ is a broader 'welcome' used for guests, events, or websites and not a standard retail greeting.
ウェルカム
ようこそ is a fixed greeting said directly to arriving guests ('Welcome!'), whereas ウェルカム functions as a noun or modifier rather than a spoken greeting.

Derived from the adverb よく (well) and the emphatic particle こそ. Originally meant 'indeed well (that you came)', and became a fixed greeting.