'Widow' in the Bible

So David went there with his two wives, Ahinoam the Jezreelite and Abigail, the widow of Nabal the Carmelite.

his second was Chileab,by Abigail, the widow of Nabal the Carmelite;the third was Absalom,son of Maacah the daughter of King Talmai of Geshur;

So Nathan went to his house.Then the Lord struck the child that Uriah’s widow bore to David, so that he was very sick.

And the king said unto her, What aileth thee? And she answered, I am indeed a widow woman, and mine husband is dead.