LOL means different things! Lots of love ETC

I have always wondered why some Nigerians (and I do mean Nigerians) tend to say 'severally' for instance "I have told you severally" rather than 'several times'.
I cannot help, but wonder how this manner of speaking developed. Apart from the fact that it does not sound right, it is in my opinion just wrong, it is simply incomplete! Watch any Nigerian movie and you will hear this phrase.
As a Nigerian living in the UK, I enjoy watching Naija movies on the Nollywood channel, but on occasions, I have had to explain to non Nigerian when the word 'severally' is uttered.
I accept that there are some unique words that Nigerians use, especially when we talk to one another, but to use this word in this manner is rather bemusing to say the least. I am also a 'product' of Nigerian education, but I know that this word just doesn't sound right when used in this manner.