v. t. [ 1st pref. un- + learn. ] [ 1913 Webster ]
I had learned nothing right; I had to unlearn everything. Milner. [ 1913 Webster ]
a. [ Pref. un- + learned. ]
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v. t. [ 1st pref. un- + leash. ] To free from a leash, or as from a leash; to let go; to release;
a. Not leavened; containing no leaven;
conj. [ Formerly, onles, onlesse, onlesse that, that is, in less, in a less case. See On, and Less. ] Upon any less condition than (the fact or thing stated in the sentence or clause which follows); if not; supposing that not; if it be not; were it not that; except;
☞ By the omission of the verb in the dependent clause, unless was frequently used prepositionally, -- a construction common in Shakespeare and still employed colloquially. [ 1913 Webster ]
Here nothing breeds unless the nightly owl. Shak. [ 1913 Webster ]