Laser is also an acronym.
Yes it's spelled with and S and not a Z. And don't tell me that in American English it's a Z it's not it's just flat out incorrect and a commonly circulated mistake.
Anyway. It stands for Light Amplification by Stimulated Emission of Radiation. L-A-S-E-R.
(You don't spell stimulated Zimulated do you? Now go forth and remove thyne Zs)