Webster's Revised Unabridged Dictionary · 1913

December

December (de*sem"bẽr) , proper noun

[French décembre, from Latin December, from decem ten; this being the tenth month among the early Romans, who began the year in March. See Ten.]

1.
The twelfth and last month of the year, containing thirty-one days. During this month occurs the winter solstice.
2.
Figuratively: With reference to the end of the year and to the winter season; as, the December of his life.