Precursor

Precursor or Precursors may refer to:
 * Precursor (religion), a forerunner, predecessor
 * The Precursor, John the Baptist

Science and technology

 * Precursor (bird), a hypothesized genus of fossil birds that was composed of fossilized parts of unrelated animals
 * Precursor (chemistry), a compound that participates in the chemical reaction that produces another compound
 * Precursor (physics), a phenomenon of wave propagation in dispersive media
 * Precursor in the course of a disease, a state preceding a particular stage in that course
 * Precursor cell (biology), a unipotent stem cell
 * Earthquake precursor, a diagnostic phenomenon that can occur before an earthquake
 * Gehrlein Precursor, a glider
 * LNWR Precursor Class (disambiguation), classes of passenger locomotives developed for the London and North Western Railway

Fiction

 * Precursors Halo (series), an extremely advanced race that preceded and were destroyed by The Forerunners
 * Precursor (novel), a 1999 novel set in C. J. Cherryh's Foreigner universe
 * Precursors, a fictional race (now extinct) of ancient beings in the board game Cosmic Encounter
 * Precursors, a fictional alien race in the Star Control video game series
 * Precursors, a fictional race of ancient beings in the video game Jak and Daxter: The Precursor Legacy
 * Precursors, a fictional alien race in Galactic Civilizations II: Dread Lords video game
 * Precursors, a fictional, almost extinct alien race that supposedly created humanity in the Assassin's Creed series
 * Precursors, a fictional, evil alien race that created the Kaiju in the movie Pacific Rim and its sequel Pacific Rim: Uprising
 * Precursors, a fictional and extremely advanced alien race in the video game Subnautica.

Other

 * Precursors of film
 * The Precursors (video game), a video game from Kyiv-based developer Deep Shadows