Nisan was the first month of the Jewish sacred year, corresponding approximately to April. Passover occurred during this month; it was also called Abib in the Pentateuch.
Definition
The Ninevites were the inhabitants of Nineveh.
Biblical Usage
Jesus referred to the Ninevites as those who repented at Jonah’s preaching, making their response a witness against those who rejected His message.
Historical Bible Dictionaries
Smith's Bible Dictionary
the inhabitants of Nineveh. (Luke 11:30)
International Standard Bible Encyclopedia (ISBE)
<p>nin'-e-vits (Nineu(e)itai): Only in Lu 11:30. The parallel passage (Mt 12:41), with Lu 11:32, has the fuller form, "men of Nineveh," which gives the meaning.</p>