Null

Null may refer to:

Science, technology, and mathematics

Astronomy

  • Nuller, an optical tool using interferometry to block certain sources of light

Computing

  • Null (SQL) (or NULL), a special marker and keyword in SQL indicating that a data value does not exist, is not known, or is missing
  • Null character, the zero-valued ASCII character, also designated by NUL, often used as a terminator, separator or filler. This symbol has no visual representation
  • Null device, a virtual file that discards data written to it, on Unix systems /dev/null
  • Null pointer or reference (sometimes written NULL, nil, or None), an object pointer (or reference) not currently set to point (or refer) to a valid object

Linguistics

  • Null (linguistics) (sometimes zero), a segment that is not pronounced or written:
    • Null morpheme (or zero morpheme), a morpheme that has no phonetic form
    • Null coda, the coda of syllables ending in a vowel; especially in reference to languages that forbid codas
    • Null onset (or empty onset, or zero onset), the onset of syllables beginning in a vowel; forbidden in some languages
    • Null-onset letter (or zero consonant), a consonant letter that does not correspond to a consonant sound, but is required when a word or syllable starts with a vowel
    • Null-subject language, a language whose grammar permits an independent clause to lack an explicit subject; such a clause is said to have a "null subject"
    • Null copula (or zero copula), a phenomenon whereby the subject is joined to the predicate without overt marking of this relationship

Mathematics

Physics

Arts and media

People with the surname

See also