Definition of sun
(Entry 1 of 3)
1a
often capitalized
: the luminous celestial body around which the earth and other planets revolve, from which they receive heat and light, which is composed mainly of hydrogen and helium, and which has a mean distance from earth of about 93,000,000 miles (150,000,000 kilometers), a linear diameter of 864,000 miles (1,390,000 kilometers), and a mass 332,000 times greater than earth
b
: a celestial body like the sun : star
2
: the heat or light radiated from the sun
played in the sun all day
3
: one resembling the sun (as in warmth or brilliance)
4
: the rising or setting of the sun
from sun to sun
in the sun
under the sun
: in the public eye
: in the world : on earth
sun
verb
sunned; sunning
Definition of sun (Entry 2 of 3)
: to expose to or as if to the rays of the sun
: to sun oneself
Sun
abbreviation
Definition of Sun (Entry 3 of 3)
Sunday
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Merriam-Webster unabridged
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The first known use of sun was before the 12th century
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