1. glowing, warmly enthusiastic praise
2. a formal expression of praise
Etymology: 1580s, Latin encomium, from classical Greek encomion, the praise of a person or thing.
My Webster's Ninth New Collegiate Dictionary (well, it was new-ish when I went to college...) says the following:
Synonyms encomium, eulogy, panegyric, tribute, citation mean a formal expression of praise.
Encomium implies enthusiasm and warmth in praising a person or thing.
Eulogy applies to a prepared speech or writing extolling the virtues and services of a person.
Panegyric suggests an elaborate often poetic compliment.
Tribute implies deeply felt praise conveyed either through words or through a significant act.
Citation applies to the formal praise accompanying the mention of a person in a military dispatch or in awarding an honorary degree.