noun a twelfth part of the heavens; a house. ·see 1st house, 8.
2. mansion ·vi to dwell; to reside.
3. mansion ·noun a dwelling place, whether a part or whole of a house or other shelter.
4. mansion ·noun the place in the heavens occupied each day by the moon in its monthly revolution.
5. mansion ·noun the house of the lord of a manor; a manor house; hence: any house of considerable size or pretension.