na.si denotes atmospheric mist or cloud-like vapor rising from the earth in the cited verses.

The attested plural noun denotes atmospheric mist or cloud-like vapor, especially as something caused to rise from the earth; Proverbs 25:14 places it with wind and rain in a weather image.

1. Rising atmospheric mist or cloud-like vapor · dominant

   All four occurrences use the common masculine plural absolute form in weather-related clauses. In Jeremiah 10:13, Jeremiah 51:16, and Psalm 135:7 the APB renders mist as rising from the earth alongside lightning, rain, and wind; in Proverbs 25:14 it renders “Clouds and wind without rain” in a comparison about a deceptive gift.

   Jeremiah 10:13Jeremiah 51:16Proverbs 25:14Psalm 135:7

In the Anselm Project Bible: The APB presents the term as “mist” in Jeremiah 10:13, Jeremiah 51:16, and Psalm 135:7, while Proverbs 25:14 uses “Clouds” in its weather comparison. This variation does not establish separate lexical senses.