Other forms: nulls
Null is a deliberate absence of any value. Set it to null, a null check, null and void.
In programming it means the field is knowingly empty, which is different from zero and different from an empty string — and confusing the three is one of the commonest sources of bugs. Its inventor called it his billion-dollar mistake. In law, null and void means having no legal force. In statistics, the null hypothesis is the assumption of no effect.
1nounnullA deliberate absence of any value.
“If the customer has no phone number, the database stores a null in that field.”
2adjectiveforceHaving no legal force.
“The judge declared the agreement null and void because one side had lied.”
null is an absence of value.
Latin nullus means none — ne plus ullus, any. Annul, nullify and none come from the same nothing.
Latin
nūllus
Middle French
nul
English, today
null
Borrowed from Middle French nul, from Latin nūllus.
Etymology from Wiktionary, CC BY-SA