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astronautical

or as·tro·nau·tic

[as-truh-naw-ti-kuh l, -not-i- or as-truh-naw-tik, -not-ik]
adjective
  1. of or relating to astronautics or astronauts.

Origin of astronautical

astronautic (< French astronautique, equivalent to astronaute (astro- astro- + -naute < Greek naútēs sailor, on the model of aéronaute aeronaut) + -ique -ic) + -al1
Related formsas·tro·nau·ti·cal·ly, adverb
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018