The original place name is ɛnkɔŋʉ́ ɛ́ mʉny, literally the eye of the rhinoceros but functionally Rhinoceros Spring; an alternative name is ɔlchɔ́rrɔ ɛ́ mʉny (olchorro is a synonymn of enkong'u).

Seemingly the British found enkong'u e muñ too difficult to pronounce.

A widespread false etymology is linked with the knuckle shape of the hills.

The Ngong Hills, from the westward slopes, overlook the Great Rift Valley dropping over 4,000 feet below, where nomadic Maasai live.

Ngong has a train station on the Nairobi–Malaba Standard Gauge Railway, which was inaugurated in October 2019.