Yes, sun is playable
...and is worth 5 points.
Found in the following dictionaries
Enable (Words with friends)
SOWPODS (Collins Scrabble Words)
OTCWL2014 (NASPA Word List 2014)
TWL06 (NASPA List 2006)
"Sun" Definition
noun
A star that is the basis of the solar system and that sustains life on Earth, being the source of heat and light. It has a mean distance from Earth of about 150 million kilometers (93 million miles) a diameter of approximately 1,390,000 kilometers (864,000 miles) and a mass about 330,000 times that of Earth.
A star that is the center of a planetary system.
A sunlike object, representation, or design.
The radiant energy, especially heat and visible light, emitted by the sun; sunshine.
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.
idiom
In the sun In the public eye.
Under the sun On the earth; in the world.
verb-intransitive
To expose oneself or itself to the sun.
verb
To expose to or as if to the rays of the sun.
abbreviation
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