What is the meaning of the suffix '-ory' (laboratory, conservatory)?

Solution 1:

The suffix is -ory meaning pertaining to, serving for;often added to words of Latin origin, but used with other words also:

adjective and noun suffix, "having to do with, characterized by, tending to, place for," from Middle English -orie, from Old North French -ory, -orie (Old French -oir, -oire), from Latin -orius, -oria, -orium.

(Etymonline)