means The lowest or worst point of something; also the hard inner seeds of certain fruits, the depressions on a surface, or the area beside a racetrack where cars are serviced.

from From Old English 'pytt,' a hole or hollow dug in the ground, likely borrowed early from Latin 'puteus,' a well or pit. The fruit-stone sense traveled in from Dutch 'pit,' meaning kernel or core. The racing 'pits' grew from the same hole-in-the-ground idea — early track service areas were literally sunken trenches beside the course. And the slangy 'the pits' for the absolute worst? That's a 20th-century American figure of speech, the lowest place you can sink.