What does "spurious" mean?

Spurious: Not legitimate; bastard; as, spurious issue. "Her spurious firstborn." Milton. Spurious primary, or Spurious quill (Zoöl.), the first, or outer, primary quill when rudimentary or much reduced in size, as in certain singing birds. -- Spurious wing (Zoöl.), the bastard wing, or alula. -- Spu"ri*ous*ly, adv. -- Spu"ri*ous*ness, n.

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