observar  to observe

obter  to get/obtain

ocorrer  to occur/happen

ocupar  to occupy/take up

odiar  to hate

ofegar  to gasp/pant

oferecer  to offer

olhar  to look

omitir  to omit

operar  to operate/perform surgery

opor  (to oppose)

optar  (to choose/opt)

ordenar  (to order/organize)

organizar  (to organize)

ouvir  (to hear/listen)