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The term astrophysical neutrino naturally refers to a neutrino other than those from Earth (from radioactive decay, human activities such as nuclear reactors, and reactions on Earth from cosmic rays), and typically also is meant to exclude the two well-known sources that produce the majority of neutrinos reaching Earth: the cosmic neutrino background, and solar neutrinos. Both these excluded populations have limited kinetic energy, and the term astrophysical neutrino often is used to mean higher energy than solar (though this could conceivably exclude some neutrinos from distant sources that happen to have lower energy). To study the astrophysical phenomena that created such a neutrino, using other astronomical observations as well (multi-messenger astronomy), its trajectory must be known well enough to identify the source by other means, and the term astrophysical neutrino is sometimes meant to imply something of the neutrino's trajectory has been determined. Astrophysical neutrino research progress has been limited in the past because handling their rarity and high energy, as well as determining their trajectory, all demand large, expensive detectors.
Some other neutrino terms regarding their sources that are also generally associated with more specific energy intervals: extragalactic neutrino, cosmological neutrino, GZK neutrino (aka cosmogenic neutrino), the latter presumed to be a product of the GZK effect.