From the mid-15 century, "plot where
plants are raised from seeds," from Latin seminarium "plant nursery,
seed plot," figuratively, "breeding ground," from seminarius of
seed, from semen (genitive seminis). It is also a school for
training priests and commonly used for any school (especially
academies for young ladies) from 1580s to 1930s.
Also commonly
used today to describe where business people go to waste time and
money.