The meaning of “נָחָשׁ”

“And Nahash the Ammonite answered them, On this condition will I make a covenant with you, that I may thrust out all your right eyes, and lay it for a reproach upon all Israel.”

“And Absalom made Amasa captain of the host instead of Joab: which Amasa was a man’s son, whose name was Ithra an Israelite, that went in to Abigail the daughter of Nahash, sister to Zeruiah Joab’s mother.”

“And David said, I will shew kindness unto Hanun the son of Nahash, because his father shewed kindness to me. And David sent messengers to comfort him concerning his father. So the servants of David came into the land of the children of Ammon to Hanun, to comfort him.”