Noun
helek (plural halakim)
(Judaism) A unit of time equal to the eighteenth part of a minute (3⅓ seconds)
Every hour is divided into 1080 halakim (singular: helek ) or parts. Source: Internet
The ultimate ancestor of the helek was a small Babylonian time period called a barleycorn, itself equal to 1 / 72 of a Babylonian time degree (1° of celestial rotation). Source: Internet