The constellation known as the Crab is on the meridian on March 15. The zodiacal symbol represents the claws of the crab. Since its motion northward then backwards to the south like a crab it developed this name. About 2500 years ago the Sun reached its most northerly position in the sky -- called the summer solstice -- when it was in front of this group of stars. On the summer solstice, about June 21, the Sun is overhead at noon at latitude 23.5 degrees north on Earth. This is called the Tropic of Cancer. (Today this position lies in the constellation Gemini due to the shifts of precession. The astrological period called Cancer begins on June 21.)
Tropic of Cancer the parallel of latitude 23°27' north of the equator, the northern boundary of the Torrid Zone, and the most northerly latitude at which the sun can shine directly overhead.
The crab has two claws by which it grasps something and holds it firmly and it also refers to things with hard shells.
Egyptian’s name for the constellation of Cancer is Klaria, meaning "The Folds," "The Resting-Places." The seventh day of Cancer was God’s day of rest.
Rest (Heb. menuwchah, men-oo-khaw', or menuchah, fem. of Heb. Manowach, maw-no'-akh, Manoah; thus meaning rest, repose, rest (-ing place); also see Heb. nuah, menuhah, peace, quiet, Gr. anapausis, katapausis). It is used of God as resting from his work (Gen. 2:2 Heb. shabath, shaw-bath', a primary root, to repose, desist), and as having his rest in the temple (1 Chron. 28:2 Heb. menuwchah). God commanded that the seventh day was to be one of rest (Exod 16:23; 31:15 Heb. shabbathown, shab-baw-thone', from Heb. shabbath, shab-bawth', from Heb. shabath, intermission, the Sabbath, rest, or special holiday) and that the land was to have its rest every seventh year (Lev. 25:4).
The Resting Places from the Holy Bible:
The Fold of Flocks from the Holy Bible:
Figuratively, Israel and the church are counted as flocks, and God is the Good Shepherd (Isa. 40:11; Matt. 26:31; Luke 12:32; 1 Peter 5:2-3).
(fold - O.T. Heb. naveh, naw-veh', or fem. navah, naw-vaw', at home, of God (temple), prepare an habitation;
In the N.T. Gr. aule, ow-lay', from the same as Gr. aer (as open to the wind), by implication a mansion, court, [sheep]fold, hall, palace.)
In Syriac (ancient Aramaic language spoken in Syria from the 3rd to the 13th century) Cancer’s name is Sartano, which means "The One Who Holds". The Romans related Cancer to Noetic forms, Khan, which means "The Traveler’s Resting Place" and ker or cer, which means "Embraced," or "Encircled." Thus Khan-Cer or Cancer, as the Romans used it, means "The Traveler’s Resting Place for the Encircled" or the "Embraced."