The Collaborative International Dictionary
Insessorial
Insessorial \In`ses*so"ri*al\, a. (Zo["o]l.)
Pertaining to, or having the character of, perching birds.
Belonging or pertaining to the Insessores.
Wiktionary
insessorial
a. pertaining to a member of the Order ''Insessores'', or perching birds; perching or designed for perching