Definition of passéist in US English:

passéist

(also passéiste)

adjective

  • Having an excessive regard for the traditions and values of the past; backward-looking. Chiefly in contrast to futurist.

noun

  • A person, especially a writer or artist, with excessive regard for the traditions and values of the past; a backward-looking person. Chiefly opposed to futurist.

Origin

Early 20th century; earliest use found in The Observer. From French passéiste from passé the past + -iste, after Italian passatista (F. T. Marinetti et al. Contro Venezia Passatista in Manifesti del Futurismo 32).