From The Collaborative International Dictionary of English v.0.48:
Quasi \Qua"si\ [L.]
As if; as though; as it were; in a manner sense or degree;
having some resemblance to; qualified; -- used as an
adjective, or a prefix with a noun or an adjective; as, a
quasi contract, an implied contract, an obligation which has
arisen from some act, as if from a contract; a quasi
corporation, a body that has some, but not all, of the
peculiar attributes of a corporation; a quasi argument, that
which resembles, or is used as, an argument; quasi
historical, apparently historical, seeming to be historical.
[1913 Webster]