Etymology of the word "tanggol"?

My mother was watching the new teleserye, Batang Quiapo, and she told me about the show's protagonist, nicknamed "Tanggol". She translated the name as "protector", but earlier this week, she said she mistranslated it, and it instead meant "defender". So it started a discussion between the two of us on what exactly the difference is between the two words. She said she wasn't really sure what the nuances of "Tanggol" were, so I'm curious what exactly the word means, where it came from, and if it has the same ambiguity as "protector" and "defender" in English.