ETYM Latin nullus not any, none; ne not + ullus any, a dim. of unus one; cf. French nul. Related to No, and One, None.
1. Having no legal or binding force; invalid.
2. Amounting to nothing; nil.
3. Having no value; insignificant.
4. Of no legal or binding force or validity; of no efficacy; invalid; void; nugatory; useless.

1. A condition, such as balance, which results in a minimum absolute value of output.
2. A condition of a radio receiver when minimum or zero signal is received
3. A minimum or zero value of an electric current or of a radio signal

To make null