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pen·to·bar·bi·tal sodium

(pĕn′tə-bärbĭ-tôl′, -tăl′)

A barbiturate, C₁₁H₁₇N₂O₃Na, that takes effect relatively rapidly, used as a sedative, a hypnotic, and an anticonvulsive drug, and for euthanasia. Also called pentobarbitone.

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:

Indo-European Roots

Semitic Roots

The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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