- A bed of earth heated by fermenting manure or other
substances, and covered with glass, intended for raising early plants,
or for nourishing exotics. - A place which favors rapid growth or development; as, a
hotbed of sedition.
Meaning of 'hotbed' (Princeton's WordNet)
1 . hotbed
[ n]
Meaning (1): - a situation that is ideal for rapid development (especially of something bad)