Birth"day` , a. Of or pertaining to the day of birth, or its anniversary; as, birthday gifts or festivities.

Birth"day` (bẽrth"dā`), n.

1. The day in which any person is born; day of origin or commencement.

Those barbarous ages past, succeeded next The birthday of invention. Cowper.

"2. The day of the month in which a person was born, in whatever succeeding year it may recur; the anniversary of ones birth."

This is my birthday; as this very day Was Cassius born. Shak.

-- Webster's unabridged 1913