Definition of love in Buddhism

The definition of love in Buddhism is: wanting others to be happy.
This love is unconditional and it requires a lot of courage and acceptance (including self-acceptance).

The "near enemy" of love, or a quality which appears similar, but is more an opposite is: conditional love (selfish love).
The opposite is wanting others to be unhappy: anger, hatred.
A result which one needs to avoid is: attachment.

This definition means that 'love' in Buddhism refers to something quite different from the ordinary term of love which is usually about attachment, more or less successful relationships and sex; all of which are rarely without self-interest. Instead, in Buddhism it refers to de-tachment and the unselfish interest in others' welfare.