An Etymological Dictionary of Astronomy and Astrophysics
English-French-Persian

One of several light rays emanating from a bright light source in images taken with → reflecting telescopes. They are artifacts caused by light diffracting around the support or → spider vanes of the → secondary mirror.

→ diffraction; → spike.

1) A long, pointed → metal  → bar.
2) Physics: A → transient variation in → voltage or → current in an → electric circuit.

M.E. spik(e) from O.N. spikr "nail;" akin to M.L.G. spiker "nail."

Sixak, from six "spur, spit; thorn; any pointed thing," + -ak a suffix of similarity and nuance.

A → transient → rise in → temperature above the normal level in a medium.

→ thermal; → spike.