I have always thought the Biblical definition in Corinthians was pretty decent;
"4 Love is patient, love is kind. It does not envy, it does not boast, it is not proud. 5 It does not dishonor others, it is not self-seeking, it is not easily angered, it keeps no record of wrongs. 6 Love does not delight in evil but rejoices with the truth. 7 It always protects, always trusts, always hopes, always perseveres.
8 Love never fails. But where there are prophecies, they will cease; where there are tongues, they will be stilled; where there is knowledge, it will pass away."
Interesting how this version of translation juxtaposes "truth" with "evil". Aside from that semantic liberty, this definition seems pretty straight to me.