Yes, it means "of the Nile" or "born of the Nile". Sometimes also rendered as "mosis" or "meses". It's like the term "ben" in Hebrew, e.g. David ben Gurion. For pharaohs the usage and interpretation would be Thutmosis (Thoth born of the Nile), or Ramses (Ra moses, "lose the o" - Ra born of the Nile). Fascinating stuff.
Yes I know. :-)