Webster's Revised Unabridged Dictionary · 1913

Except

Except , transitive verb

[Latin exceptus, past participle of excipere to take or draw out, to except; ex out + capere to take: compare French excepter. See Capable.]

1.
To take or leave out (anything) from a number or a whole as not belonging to it; to exclude; to omit.
Who never touched The excepted tree. — Milton
Wherein (if we only except the unfitness of the judge) all other things concurred. — Bp. Stillingfleet
2.
To object to; to protest against. [Obsolete] — Shakespeare

Except , intransitive verb

To take exception; to object; -- usually followed by to, sometimes by against; as, to except to a witness or his testimony.
Except thou wilt except against my love. — Shakespeare

Except , preposition

[Originally past participle, or verb in the imperative mode.]

With exclusion of; leaving or left out; excepting.
God and his Son except, Created thing naught valued he nor... shunned. — Milton

Except (ek*sept") , conjunction

Unless; if it be not so that.
And he said, I will not let thee go, except thou bless me. — Gen. xxxii. 26
But yesterday you never opened lip, Except, indeed, to drink. — Tennyson

As a conjunction unless has mostly taken the place of except.