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A back-formation from MACHO, which is used as an acronym for massive compact halo object. Words used to fill in the apparently missing "A" word include astrophysical and astronomical.
Etymology from Wiktionary, CC BY-SA 4.0.
A back-formation from MACHO, which is used as an acronym for massive compact halo object. Words used to fill in the apparently missing "A" word include astrophysical and astronomical.
Etymology from Wiktionary, CC BY-SA 4.0.