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.
My grandmother will celebrate her 100th birthday next month.
A party was held to celebrate the centenarian's birthday.
centenarian
Compound of 百 (hundred) and 寿 (longevity, congratulations). The term is a modern coinage for reaching the age of 100, often used in celebratory contexts.