(telecommunications) end of message.

The decade of the 1930s. / Temperatures from 30 to 39 degrees. / Ages from 30 to 39. / The numbers from 30 to 39.

Alternative spelling of 30s

(Canada, US, journalism) Indicates the end of a story, article, or press release that is submitted for editing and typesetting.

(physics) A minor stable isotope of silicon, ³⁰₁₄Si, having fourteen protons and sixteen neutrons; it amounts to 3% of the element in nature

Alternative form of 30s

(cellular automata) A one-dimensional binary cellular automaton rule displaying aperiodic, chaotic behaviour.

(informal) 30 Rockefeller Plaza, a skyscraper in Midtown Manhattan, New York City, United States.

(singular only, informal, firearms) The .303 British rifle calibre. / (countable) A rifle chambered in this calibre, normally the SMLE series. / (countable, music) The TB-303 synthesizer.

(often with "the") North Central Colorado, including Denver and Boulder, after the 303 area code.