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men·stru·um

(mĕnstr-əm)

n. pl. men·stru·ums or men·stru·a (-str-ə)

A solvent, especially one used in extracting compounds from the tissues of organisms.

[Middle English, menstruation, from Medieval Latin mēnstruum, sing. of Latin mēnstrua, menses; see MENSTRUATE.]

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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