A feeling towards someone or something, a desire to have something and readiness to pay any cost. An example is someone with an idea that will benefit people, even though this is a good idea, without LOVE the individual can become selfish which means the good idea will become a self-centered idea.
This person is happy as long as his/her passion is fulfilled, so it is no longer about people, it is now just to fulfil a dream at any cost.
Passion alone is not enough because passion will give energy to the person, energy to keep going in order to keep the passion alive.
Passion without love is dangerous because love is the anchor and our guard for life.
A religious look to the definition of love can be found in the bible: 1 Corinthians chapter 13 verses 3-8.
Passion for anything will be superseded one day, but love will never end.