Abigail is from the Hebrew Avigayil ("my father's joy"). The biblical Abigail — wife of the churlish Nabal of Carmel and, after his death, of King David (1 Samuel 25); her intercession with David is among the most diplomatic moments in the Hebrew Bible. Abigail Adams (1744-1818) — wife of John Adams (2nd US President), mother of John Quincy Adams (6th US President), and the most prolific letter-writer of the American Revolution. Her March 1776 "Remember the Ladies" letter to John urging him to grant women legal status in the new republic stands as a founding document of American feminism. A top-10 US baby name from 2001 to 2017, peaking at #6 in 2005.
Subject of Edith Gelles's Abigail Adams: A Writing Life (2002).
In Pythagorean numerology the letters of Abigail reduce to 5, The Seeker. This is a traditional interpretive system, not a factual claim about the name.