(Hebrew הבל Hei, Beth, Lamed, pronounced "ha-bel") Literally, nonsense, futility, idleness, vapor, breath, vanity, to waste life on vain things. One of the sons of Adam and Eve.

"And Adam knew Eve his wife; and she conceived, and bare Cain [Kayin], and said, I have gotten a man from the LORD. And she again bare his brother Abel [Habel]. And Abel was a keeper of sheep, but Cain was a tiller of the ground." - Genesis 4:1-2

הבל הבלים אמר קהלת הבל הבלים הכל הבל - "Abel of abel, saith the Preacher, abel of abels; all [is] abel (futility)." - Ecc 1:2