menstruum

From Latin mēnstruum (“menstrual discharge”).

• (UK) IPA^(key): /ˈmɛn.stɹʊəm/

menstruum (plural menstruums or menstrua)

1. (chiefly in the plural, historical) The menses; menstrual discharge. [from 14th c.]
2. (historical) A solvent. [from 16th c.]
   • 1661, Robert Boyle, The Sceptical Chymist:

     Whenever any menstruum or other additament is employed, together with the fire, to obtain a sulphur or a salt from a body, we may well take the freedom to examine, whether or no the menstruum do barely help to separate the principle obtained by it...

   • 1665, Robert Hooke, Micrographia:

     [T]hat combustible sulphureous Body is presently prey'd upon and devoured by the aereal incompassing Menstruum, whose office in this Particular I have shewn in the Explication of Charcole.

   • 1812, Humphry Davy, The Elements of Chemical Philosophy, Introduction:

     The analysis of mineral bodies... refined by the application of acid and alkaline menstrua, by Margraaf, Bergman, Bayen, and Achard, received still greater improvements from the labours of Klaprothk, Vauquelin, and Hatchett.

3. Any liquid medium

• paramenstruum

• (Classical) IPA^(key): /ˈmen.stru.um/, [ˈmẽːs̠t̪ruʊ̃ˑ]
• (modern Italianate Ecclesiastical) IPA^(key): /ˈmen.stru.um/, [ˈmɛnst̪ruːm]

Substantive of mēnstruus (“of or pertaining to a month, monthly”), from mēnsis (“month”).

mēnstruum n (genitive mēnstruī); second declension

1. a monthly payment
2. a monthly term of office or service
3. (in the plural) menstrual discharge

Second-declension noun (neuter).

Inflected form of mēnstruus (“of or pertaining to a month, monthly”).

mēnstruum

1. inflection of mēnstruus:
   1. nominative/accusative/vocative neuter singular
   2. accusative masculine singular

• “menstruum”, in Charlton T. Lewis and Charles Short (1879) A Latin Dictionary, Oxford: Clarendon Press
• menstruum in Gaffiot, Félix (1934) Dictionnaire illustré latin-français, Hachette.
• Carl Meißner, Henry William Auden (1894) Latin Phrase-Book‎, London: Macmillan and Co.
  • monthly interest: usura menstrua
    
• “menstruum”, in Harry Thurston Peck, editor (1898), Harper's Dictionary of Classical Antiquities, New York: Harper & Brothers
• “menstruum”, in William Smith et al., editor (1890), A Dictionary of Greek and Roman Antiquities, London: William Wayte. G. E. Marindin