Light
Nearly every culture has reached for light when naming a daughter.
Light is the most widely attested idea in this library, and it is the clearest illustration of the difference between a root that was inherited and a root that was carried.
The Indo-European languages inherited theirs. Latin lūx, Greek leukós — which drifted from bright to white — and Sanskrit ruc- all descend from a single reconstructed root. That is why Lucia in Italy and a Sanskrit name built on ruc- in India are, at a distance of several thousand years, the same word. Greek supplies a second, unrelated root in phōs, and Sanskrit a second in jyotis, from a verb meaning to shine.
Arabic nūr is a different story. It belongs to the Semitic root N-W-R, which also gives Hebrew nēr, a lamp — the two are genuine cousins within Semitic. But nūr's reach far beyond that family has nothing to do with descent. It is in Turkish, Persian, Urdu, Malay, Indonesian, Hausa and Swahili because Islam is, and it arrived in each of those languages as a loanword rather than an inheritance. Noor is one of the most widely used girls' names on earth, and its distribution traces the history of a religion almost exactly.
Persian adds roshan, bright, which spread through the Persianate world into Urdu on a similar cultural current. Hebrew, Yoruba, Japanese and Finnish each name daughters for light out of their own resources entirely.
It is worth noticing what light is usually standing in for. Very few of these names are about illumination in a literal sense. They are about clarity, guidance, hope, and the ordinary relief of morning.
The same root, across a whole language family
These are attested shared morphemes — not coincidences of spelling. Where we are not confident a root is shared, we say nothing and simply list the names.