noun
centenarian; centenarianism; 100th birthday celebration
Refers to a person who has reached 100 years of age, the state of being 100, or the celebration of a 100th birthday. Often used in contexts of longevity and congratulations.
祖母は来月百寿を迎えます。
My grandmother will celebrate her 100th birthday next month.
百寿を祝う会が開かれた。
A party was held to celebrate the centenarian's birthday.