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humidity vs. dew point

humidity
[hyoo-mid-i-tee, yoo-] / hjuˈmɪd ɪ ti, ju- /

noun

humidities plural

  1. humid condition; moistness; dampness.

  2. relative humidity.

  3. an uncomfortably high amount of relative humidity.

    It's not the heat, it's the humidity that tires me out.
dew point

noun

  1. the temperature to which air must be cooled, at a given pressure and water-vapor content, for it to reach saturation; the temperature at which dew begins to form.