HuldafBrazilian (Rare) Possibly a variant of Hilda. Also, compare the names Astrid and Astrud, which could be more examples of how an I can turn into a U.
IberêmBrazilian, Tupi Originally a diminutive of Itiberê, which is said to be derived from Tupi y "water; river" and tiri'ri "to drag oneself" and is thus commonly interpreted as "creeping river".
IndaiáfBrazilian, Tupi Derived from Tupi ini'yá "thread fruit", itself derived from Tupi inĩ "hammock" and Old Tupi 'ybá "fruit", referring to the use of fruit fibers for the production of (sleeping) hammocks.
IpêfTupi Derived from Tupi ï'pe "shell (of a seed)". This is the Portuguese name for several bignoniaceae trees known for the beauty of their flowers. Moreover, the ipê was elected as the Brazilian national tree.
Irianm & fIndonesian, Brazilian (Rare), Spanish (Rare) Historical name for the island of New Guinea in Indonesian, from Biak meaning "hot land". It is also a woman-dragon character in Ursula K. Le Guin's Earthsea novels.
IzildafPortuguese (Brazilian) Variant of Isilda. This was borne by Maria Izilda de Castro Ribeiro (1897-1911), a Portuguese girl who died aged 13; she is known to Brazilian Catholics as "Menina Izildinha", and is venerated as a Brazilian folk saint.