Quaternary (disambiguation)

Look up quaternary in Wiktionary, the free dictionary.

Quaternary may refer to:

• Quaternary (or quartary), the fourth geologic time period
• The fourth Ordinal number (linguistics), coming after Tertiary
• Quaternary numeral system (base-4) in mathematics
  • Quaternary counting system in linguistics
  • Quaternary Communications Encoding, a method using 4 physical signal levels, such as 2B1Q encoding.
• Quaternary (EP), an extended play recording by Mötley Crüe
• Quaternary structure in structural biology
• Quaternary compound, in which an atom, usually carbon, is attached to four other atoms
  • Quaternary ammonium cation
• Quaternary sector of the economy, which encompasses knowledge-based services
• Quaternary stress, a proposed degree of stress in linguistics