A portable apparatus having a container with compressed air, a regulator that is equipped with a mouthpiece and adjusts the pressure of the released air to match the surrounding pressure, and often a buoyancy compensator, used for breathing under water.
[s(elf-)c(ontained) u(nderwater) b(reathing) a(pparatus).]
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Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
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