noun

• (Mormonism) A class of religious education for youths ages 14–18 that accompanies normal secular education.
• (by extension) The place or original stock from which anything is brought or produced.
  "Seeing then there is indeed a twofold Seminary or stock in nature, from whence are deriv’d the issues of love and hatred distinctly flowing through the whole masse of created things, and that Gods doing ever is to bring the due likenesses and harmonies of his workes together, except when out of two contraries met to their own destruction, he moulds a third existence, and that it is error, or some evil Angel which either blindly or maliciously hath drawn together in two persons ill imbarkt in wedlock the sleeping discords and enmities of nature lull’d on purpose with some false bait, that they may wake to agony and strife, later then prevention could have wisht, if from the bent of just and honest intentions beginning what was begun, and so continuing, all that is equall, all that is fair and possible hath been tri’d, and no accommodation likely to succeed, what folly is it still to stand combating and battering against invincible causes and effects, with evill upon evill, till either the best of our dayes be linger’d out, or ended with some speeding sorrow."
• (obsolete) Seminal state or polity.
  "The hand of God that first created the Earth, hath with variety disposed the principles of all things; wisely contriving them in their proper seminaries"
• (archaic) An academic seminar.