#0541 ἀπαύγασμα apaugasma {ap-ow'-gas-mah}

 from a compound of G0575 and G0826; TDNT - 1:508,87; n n

—Greek Word Study (Transliteration-Pronunciation Etymology & Grammar)

 1) reflected brightness
    1a) of Christ in that he perfectly reflects the majesty of God
 2) effulgence
    2a) shining forth, of a light coming from a luminous body (Vine)
    2b) out-raying (Vincent)

—Thayer's (New Testament Greek-English Lexicon)

—Strong's (Greek Dictionary of the New Testament)

—NAS Exhaustive Concordance of the Bible with Hebrew-Aramaic and Greek Dictionaries

 AV - brightness 1; 1

—Exhaustive Concordance (KJV Translation Frequency & Location)