An Etymological Dictionary of Astronomy and Astrophysics

To pack and align photons or atomic particles parallel to a particular direction.

Etymology (EN): L. collimatus, p.p. of collimare, alteration of collineare “to make straight,” from → com- + linea, → line.

Etymology (PE): From ham- “together, with,” → com- + râstâ, → direction, + -idan infinitive suffix, kardan “to do,” → work.