These names usually indicate a stopped flute similar to the Gedeckt or Stopped Diapason. According to Grove, they are sometimes used for a Chimney Flute or open conical flute (see Spitzflöte). Williams confirms this apparent contradiction: �a prefix denoting �stopped� or closed pipes. Tapadillo was a 17th-18th cent. Spanish flute of 4' pitch, stopped, open, conical, or Rohrflöte.
Tapadillo is the most common of these names; Osiris contains 42 examples, all at 4' pitch except for one at 2' pitch. Of Tapada alone we know of no examples, but Osiris contains seven examples of Octava Tapada, all at 4' pitch, and three examples of Flauta Tapada. Neither of those names are mentioned in the literature, and we assume them to be synonyms for Tapada. Only one example of Tapado is known, and five of Flautado Tapado, two at 4' and three at 8'. No examples of Tappato are known. Contributions welcome.