The term "White-winged duck" does not correspond to a widely recognized or established species or concept in major ornithological or biological databases. Accurate information is not confirmed regarding a bird species or taxonomic entity officially designated as the "White-winged duck."
It is possible that the term is a colloquial, informal, or mistaken reference to a bird with white wing markings. For example, some duck species, such as the wood duck (Aix sponsa) or certain pintails, exhibit white wing patches but are not commonly known as "White-winged ducks." Alternatively, the term might be a confusion with the "White-winged Duck" (Asarcornis scutulata), which is a real species but typically spelled without a hyphen in standard usage and more precisely referred to as the White-winged Wood Duck—though this naming overlap may contribute to uncertainty.
Due to the lack of consistent usage or authoritative references for "White-winged duck" as a distinct, recognized term, it cannot be accurately described within a formal encyclopedic context. The term may appear in regional, outdated, or non-scientific sources, but such references are not sufficient to confirm its validity as an established concept.