From The Collaborative International Dictionary of English v.0.48 [gcide]:
Vocation \Vo*ca"tion\ (v[-o]*k[=a]"sh[u^]n), n. [L. vocatio a
bidding, invitation, fr. vocare to call, fr. vox, vocis,
voice: cf. F. vocation. See Vocal.]
1. A call; a summons; a citation; especially, a designation
or appointment to a particular state, business, or
profession.
[1913 Webster]
What can be urged for them who not having the
vocation of poverty to scribble, out of mere
wantonness make themselves ridiculous? --Dryden.
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2. Destined or appropriate employment; calling; occupation;
trade; business; profession.
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He would think his service greatly rewarded, if he
might obtain by that means to live in the sight of
his prince, and yet practice his own chosen
vocation. --Sir. P.
Sidney.
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3. (Theol.) A calling by the will of God. Specifically:
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(a) The bestowment of God's distinguishing grace upon a
person or nation, by which that person or nation is
put in the way of salvation; as, the vocation of the
Jews under the old dispensation, and of the Gentiles
under the gospel. "The golden chain of vocation,
election, and justification." --Jer. Taylor.
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(b) A call to special religious work, as to the ministry.
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Every member of the same [the Church], in his
vocation and ministry. --Bk. of Com.
Prayer.
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From WordNet (r) 3.0 (2006) [wn]:
vocation
n 1: the particular occupation for which you are trained [syn:
career, calling, vocation]
2: a body of people doing the same kind of work [syn:
occupational group, vocation]