If it doesn't have a tail

In Portuguese there is only one work for "Monkey" and "Ape" (macaco).
Here's a quick song that would help you decide if you will use the word "monkey" or "ape" in English.

Lyrics here: http://veggietales.wikia.com/wiki/Monkey

O google translate traduz errado *Google translate does a poor translation job.
https://translate.google.com/translate?hl=en&sl=auto&tl=pt&u=http%3A%2F%2Fveggietales.wikia.com%2Fwiki%2FMonkey
what the world is "PARVA", google?

And one last tip. Another word that is translated as monkey (macaco) em portuguese is a Jack (the one you use in your car).

My husband just informed me people sometimes refer to people that work in cars as greased Monkeys... so... full circle, there you go.
Aparently there's even a tV show about it, I never watched, so I can't tell you to if it's good or not, but here's the show: http://www.tvguide.com/tvshows/grease-monkeys/558990/