What does Ibn Umm Maktum literally mean?

It's said that surah 80 of the Quran is revealed in regards to [Ibn Umm Maktum](https://en.wikipedia.org/wiki/Ibn_Umm_Maktum) . My question is about the meaning of the name of this person. I'm not Arab. As much as I know, Ibn means son, and Umm means mother. So, this confuses me. Does his name literally means son of the mother of Maktum? Is it a strange linguistic feature of classical Arabic?