focus

The story

1. Latin · borrowed fromfocus“hearth, fireplace”
2. English todayfocus

Borrowed from Latin focus (“hearth, fireplace”); see there for more. Related to fuel. Kepler introduced the term into mathematics and the sciences in describing elliptical orbits of planets (quote from Nicholas Mee): "One of the interesting properties of an ellipse is that if there were a light bulb at one focus, then all the light that it emits would reflect off the ellipse and converge at the other focus. This is why Kepler originally used the name focus for these points."

Words from the same roots