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uppercase letter; capital letter
large character; large writing
the (kanji) character "dai" meaning "big"
huge character "dai" formed by fires lit on the side of a mountain in Kyoto on August 16 each year
大文字で入力してください。
Please enter it in capital letters.
大文字と小文字を区別しないと通らない。
It won't work if you don't distinguish between uppercase and lowercase.
パスワードは大文字と数字を組み合わせるべきだ。
Passwords should combine uppercase letters and numbers.