Very good information! =)
- Etimologia (from Portuguese Wikipedia)
O termo "abacaxi" é oriundo da junção dos termos tupis i'bá (fruto) e ká'ti (recendente, que exala cheiro agradável e intenso), documentado já no início do séc. XIX.
O termo "ananás" (em português e espanhol) é do guarani e tupi antigo naná, e documentado em português na primeira metade do séc. XVI e em espanhol na segunda (1578), sendo empréstimo do português do Brasil ou da sua língua geral.
For the one who can't speak Portuguese, it says: The term "ananás" (or "ananas") is from the ancient Gurapani and Tupi "naná", that dates from around 1578.
So, no wonder most of the countries use "ananas", it was "naná", then a Portuguese word that was borrowed in most of the language, as this fruit wasn't known before by the people who took this word. "Pineapple" is relative to the shape.
I just started the Guarani from Spanish course. Both are awesome! :)
At this point it all became quite confusing, maybe because I have some experience with the Greek alphabet, but I always miss the point here... The task is to translate, but I always want to just re-write the given word, and I realized it after 'alfa/alpha' and ananas... It's not good or bad, just weird :)
Try wiktionary, you should be able to identify genders by m, f, n there. For example μήλο. As a dictionary it's not amazing so I'd use wordreference but it should be good enough for the genders. Wordreference (apple) does include the genders but only in Greek! αρσ(ενικό)=masculine, θηλ(υκό)=fenimine and ουδ(έτερο)=neuter.