D defs.my
Entry 1 sense Webster, 1913

astronautics

· as·tro·naut·ics · IPA /ˌæstrənˈɑtɪks/
01 n. The theory and practice of navigation through the upper atmosphere or outer space; the science of travel beyond the Earth's atmosphere.
  1. 1.
    The theory and practice of navigation through the upper atmosphere or outer space; the science of travel beyond the Earth's atmosphere.