Glennan is actually a not uncommon name in Ireland. It is of Scottish origin, and an Anglicized version of Mac Gille Fhinneain. Medieval scholars dropped the 'Mac' (meaning 'child of', and started spelling Gille Fhinneain phonetically. The Gaelic pronunciation of the words sounds sort of like 'gil-hinaan', which in time got shortened to 'glinaan', which is the pronunciation used in the show.
Her full name: Princess Fiona Fiona O_O
Fiona Cheeks's birth name is Larissa Kelley.
Fiona Lincke's birth name is Fiona Mary Lincke.
Fiana Toibin's birth name is Fiona Jude Toibin.
Fiona Bones is 163 cm.
Fiona Coyne .
Fiona Apple - singer
Her full name: Princess Fiona Fiona O_O
Fiona Cheeks's birth name is Larissa Kelley.
Fiona Wood's full name is Fiona Melanie Wood.
Fiona Gubelmann's birth name is Fiona Victoria Gubelmann.
Fiona Lewis's birth name is Fiona Marie Lewis.
Fiona Apple's birth name is Fiona Apple Maggart.
Fiona Dolman's birth name is Dolman, Fiona Jane.
Fiona Ferrer's birth name is Fiona Ferrer Leoni.
Fiona Frawley's birth name is Fiona Anne Frawley.
Fiona Crossley's birth name is Fiona Mary Crossley.