Definitions only work when some person or a group of persons give a definition which others agree to abide by in their conversation together. This happens in the sciences, but meanings get fouled up when there is a model shift as from Newton to Einstein and suddenly words like mass, gravity, acceleration, and velocity subtly change their meaning. Eventually scientists try to drill one language game into all practitioners of that science.
Most of our conversation is using words that we understand with that person in that context, and when there is a misunderstanding we can try to explain. There are only a few definitions in the New Testament.
In 1 Corinthians 13 we have one such attempt to give a definition of what Paul's view of love is. Jesus also used parables to clarify the use of a word as the word "neighbor" in the parable of the Good Samaritan. Obviously the definitions found in dictionaries only reflect some common uses of the words listed.
What then do we do when we are trying to do understand the New Testament use of the word "love" in a particular situation - loving enemies, loving God, loving a wounded person on the road, loving other Christians. The art is to try to picture how the writer and the Christian group he belonged to was wanting to use the word. That is why the New Testament cannot be understood from outside a personal experience of the love of God and the resultant love for others. And even with a personal experience of the love of God we may need to have the meaning of the words clarified by further Bible study and the illumination of the Holy Spirit.
When we move to adopting a theological model (mine is called Creative Love Theism) we inevitably try to fit the use of words in each text into an explanatory model that we intend to use in preaching. That is why to my mind being self-conscious about the model we are using (and the other models people use) helps us understand what others are doing with that text.
But we have no proof that we are right, and we certainly have no definition
we can use across the board and in all situations. The definitions that
we find in theological books only apply in a discussion with that writer
and perhaps in the denominational group he or she belongs to.