a low price, level, or value [≠ high]
fall to/hit/reach etc a new low (=be worth less than ever before)
The euro has fallen to a new low against the dollar.
Public confidence in the legal system is at an all-time low (=much lower or worse than ever before).
a very difficult time in someone's personal or working life
highs and lows (of something) (=good times and bad times)
the highs and lows of an actor's life
the lowest point that the temperature reaches during a particular time [≠ high]:
The overnight low will be 8° C.
an area of low pressure in the air [≠ high]:
a low moving in over the Pacific
someone you think is completely unfair, cruel, immoral etc
someone from a low social class - often used humorously