To view a Portuguese dictionary, you can access one for free online, go to a library, or purchase one online or at a book store. Popular online Portuguese dictionaries include Infopedia.pt, PortugueseDictionary.net, WordReference.com, Aulete.com/br, Lexico.pt.
Infopedia provides translations to and from English and five other languages. PortugueseDictionary is a Portuguese-English and English-Portuguese dictionary which offers basic translations and word meansings. Wordreference features Portuguese-English, English-Portuguese, and Portuguese-Spanish dictionaries. Aulete and Lexico are only in Portuguese.
There are also smart phone app dictionaries that can be downloaded for free, such as those by SE Develop. If you want to purchase a dictionary online, a good option for Portuguese only is the Aurélio Dicionário da Língua Portuguesa, and a good multilingual dictionary is the Larousse Pocket Dictionary.