đa

Etymology 1
The Northern Middle Vietnamese form is attested in Dictionarium Annamiticum Lusitanum et Latinum (1651), points to the earlier form. The "modern" Northern-Southern reflex da is attested in Dictionarium anamitico-latinum (1838) and continued to be used as late as works of from the 1920s.

Considering that de Rhodes' dictionary was chiefly based on one or several Northern dialects that had undergone lenition quite throughout, the modern form đa without lenition might have spread from a Central dialect less affected by it.

Noun

 * 1)  banyan

Etymology 2
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