Apart from the difficulty of their not being traceable in the Orient under that name, Maria Carbonell Pico’s A terminologia naval Portuguesa anterior a 1460, Lisbon 1963, does not record parao as a term in use in Portugal itself.

The solution to this puzzle may lie in the Etymologies of Isidore of Seville, (ca 600AD, Latin text in J-P Migne, Patrologiae Cursus Completus, Paris 1839, Ser.2, Vol.82, Bk.XIX, Ch.I), where paro is a vessel suitable for use by pirates. His source is primarily Cicero, and the word has a Greek root. A swift, "wave-impelling", undecked type is implied. The major texts we have for the Portuguese arrival in India were all composed somewhat after the event, and by literate men, not seamen. It seems at least possible that these writers have simply taken the old and perhaps obscure Latin term for pirates’ vessels from Isidore/Cicero, and this name has stuck, as a generic, even when the type or types were in use by their allies or adopted by the Portuguese themselves.

Carbonell Pico only records forms based on curs- for piracy; Leitão & Lopes recognise paró, but only as a direct equivalent of parau.

It is also possible that the term prahu, phonetically somewhat similar, may have been heard by the newly arrived Portuguese, as a term for the functionally similar types occurring much further East, and that this triggered the association with paro. Whether the prahus themselves ever reached Western India is doubtful, but the Portuguese would certainly have encountered them long before the first chronicles were written down.