"namelijk" sometimes literally means "namely" or "to be specific", "to be precise" (although these last two phrases could be translated as "om specifiek te zijn", "om precies te zijn"). In this case, "namelijk" is typically preceded by a comma and followed by a noun or an enumeration. From a dictionary: "er was één tegenstemmer, namelijk de voorzitter" "er zijn drie afmeldingen, namelijk Peter, Juan en Bob" In the sentence you provided, it has a different meaning. The sentence containing "namelijk" provides an explanation/elucidation for what has been said earlier, typically the sentence right before. This is signaled by the fact that it appears right after the first verb in the sentence (in this case "heb"). This is a very common usage of "namelijk". Using "namelijk" provides a way of starting a new sentence that explains the one before, without starting it with "Want" or "Omdat", which would look or sound awkward. It's difficult to translate to English. The best I can think of is to use the construct "This is because". "Ik heb veel gevlogen. Ik ben namelijk stewardess geweest." "I've flown a lot. This is because I've been a flight attendant." From a dictionary: "Neem je paraplu mee, het gaat namelijk regenen." "We moeten opschieten, de trein vertrekt namelijk over tien minuten." In this kind of conversational language, "this is because" would sound very awkward I think. I'd translate it like this: "Take your umbrella with you. It's gonna rain, you know." "We need to hurry. The train leaves in ten minutes, you see." In many instances, I think "namelijk" can be left out without causing much harm. Then it's left up to the reader or listener to infer that the current sentence explains something about the earlier one.