noun
88th birthday; celebration of one's 88th year
Refers to the 88th birthday celebration in Japanese culture, derived from the kanji 米 which can be broken down into 八十八 (88).
祖父は今年米寿を迎えます。
My grandfather will celebrate his 88th birthday this year.
米寿のお祝いに家族が集まった。
The family gathered to celebrate his 88th birthday.