The Collaborative International Dictionary of English v.0.48:

Devotion \De*vo"tion\, n. [F. d['e]votion, L. devotio.]
   1. The act of devoting; consecration.
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   2. The state of being devoted; addiction; eager inclination;
      strong attachment love or affection; zeal; especially,
      feelings toward God appropriately expressed by acts of
      worship; devoutness.
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            Genius animated by a fervent spirit of devotion.
                                                  --Macaulay.
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   3. Act of devotedness or devoutness; manifestation of strong
      attachment; act of worship; prayer. "The love of public
      devotion." --Hooker.
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   4. Disposal; power of disposal. [Obs.]
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            They are entirely at our devotion, and may be turned
            backward and forward, as we please.   --Godwin.
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   5. A thing consecrated; an object of devotion. [R.]
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            Churches and altars, priests and all devotions,
            Tumbled together into rude chaos.     --Beau. & Fl.
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   Days of devotion. See under Day.

   Syn: Consecration; devoutness; religiousness; piety;
        attachment; devotedness; ardor; earnestness.
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WordNet (r) 3.0 (2006):

devotion
    n 1: feelings of ardent love; "their devotion to each other was
         beautiful" [syn: devotion, devotedness]
    2: commitment to some purpose; "the devotion of his time and
       wealth to science"
    3: religious zeal; the willingness to serve God [syn:
       idolatry, devotion, veneration, cultism]
    4: (usually plural) religious observance or prayers (usually
       spoken silently); "he returned to his devotions"