A yourmometer is a tool used in measuring unintentional profanity. The units of measurement, obviously, are Yourms.
A typical yourmometer combines the functions of a bathroom scale, a bomb calorimeter, a colorimeter, and an uglimeter. Advanced models may include a penile plethysmograph, particularly for the measurement of your mom when she is equipped with a penis; or a built-in breathalyzer or drug test for when your mom is so drunk or smokes so much crack.
A primitive yourmometer may be constructed with parts that can easily be found in the home; for instance, my finger, which may typically be found in your mom. When the yourmometer is pointed at your mom, it makes a "beeping" noise indicating that ... uh, your mom. When it is pointed at your dad, you, or me, it makes a "woo" noise indicating the absence of your mom. Except when I'm doing your mom.