Strong's numbers

זִיו (H2122)

zîyv

zeev

(Aramaic) corresponding to זִו; (figuratively) cheerfulness; brightness, countenance.

[זִיו] n.m. brightness, splendour

From Brown, Driver, and Briggs, A Hebrew and English Lexicon of the Old Testament (1906), in the public domain.

Shown in the King James Version (KJV), whichever translation you read in — it is the text these numbers are tagged against.

Daniel 2:31
Thou, O king, sawest, and behold a great image. This great image, whose brightness was excellent, stood before thee; and the form thereof was terrible.
Daniel 4:36
At the same time my reason returned unto me; and for the glory of my kingdom, mine honour and brightness returned unto me; and my counsellors and my lords sought unto me; and I was established in my kingdom, and excellent majesty was added unto me.
Daniel 5:6
Then the king's countenance was changed, and his thoughts troubled him, so that the joints of his loins were loosed, and his knees smote one against another.
Daniel 5:9
Then was king Belshazzar greatly troubled, and his countenance was changed in him, and his lords were astonied.
Daniel 5:10
Now the queen, by reason of the words of the king and his lords, came into the banquet house: and the queen spake and said, O king, live for ever: let not thy thoughts trouble thee, nor let thy countenance be changed:
Daniel 7:28
Hitherto is the end of the matter. As for me Daniel, my cogitations much troubled me, and my countenance changed in me: but I kept the matter in my heart.