It seems that $\textrm{eV}\!/c^2$ (and its multiples) is commonly used as the unit of mass in particle physics. For example, David Griffiths uses it quite naturally in Introduction to Elementary Particles, so does Wolfram Alpha.
However, a problem occurs when one is to pronounce a quantity expressed in this unit. My question is: What is the common, or most widely used pronunciation of this unit? Is it even ever pronounced? Video or audio recordings to back up individual cases are welcome.
Answer
I say "ee-vee per see-squared" or "ee-vee over see-squared."
If it's convenient to assume $c=1$, I'll say "ee-vee" or "electron volts." I can't remember ever having said "electron volts over see-squared."
For MeV and GeV I'll say "em ee vee" or "gee ee vee." I know people who say "mev" or "jev", to rhyme with the first syllable of "Beverley", but in low-energy nuclear physics they're in a minority.
Tangential to your question, essentially everyone I know (US/Canada bias) says giga as /ˈɡɪɡə/ with two hard G sounds, rather than /ˈdʒɪɡə/ with an initial J sound. This is probably why "jev" grates on me so hard.
When I'm talking about cold neutron reactions I have to be careful to distinguish between milli-ee-vee (meV) and mega-ee-vee (MeV), since both scales occur in the same reaction. Occasionally I'll say "milli electron volts" (or similar), if I especially want to emphasize the energy to the listener.
When I'm talking to someone who's not a physicist, I'll sometimes say "Energy is measured in volts" and then talk about volts, megavolts, etc.
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