'Weeks' in the Bible

Seven weeks shalt thou number unto thee: from the time thou beginnest to put the sickle to the standing grain shalt thou begin to number seven weeks.

And thou shalt keep the feast of weeks unto Jehovah thy God with a tribute of a freewill-offering of thy hand, which thou shalt give, according as Jehovah thy God blesseth thee:

Three times in a year shall all thy males appear before Jehovah thy God in the place which he shall choose: in the feast of unleavened bread, and in the feast of weeks, and in the feast of tabernacles; and they shall not appear before Jehovah empty: