‘Unconditional love’ is a phrase rather than a single word, but as it’s a unified concept I think it’s fair game.
The idea is perennially lauded as a high virtue, particularly among those singing the praises of pets, parents, and deities. (Finding the hidden associations between those concepts is left as an exercise for the student.) Any difficulty or uncertainty is bandaged over with the assertion that the entity in question gives/receives unconditional love, and so all problems are obviated.
I don’t think many people actually consider the implications of releasing any state from conditionality, much less love itself. If it is unconditional, it can have no necessary requirements. No change in the subject of the state can affect the state – so it wouldn’t matter what the subject does or becomes, it would be loved just as unconditionally. People find that comforting, not considering that the subject could be unrecognizably altered, or even replaced, and be just as loved as before. They want to be able to make mistakes or act against the love, and receive it regardless, but they also want to be loved for who and what they are – and those desirable qualities are mutually incompatible. If you’re loved without conditions, you aren’t what’s loved. The subject is arbitrary, the emotional response indiscriminate; your absence is appreciated just as deeply as your presence, the passion directed blindly at whatever happens to be available.
Responses are valuable because they are specific. People care about their pets’ love precisely because their loyalty and affection are NOT unconditional; the same is true of friends, parents, and lovers. Their object cannot be arbitrarily changed or replaced and receive the same response. Our behavior towards them must fit within certain parameters to maintain the state. We don’t value what is free, what we can acquire without effort or cost. We want to be considered special and unique, not interchangeable, and that requires that we be valued for specific properties we possess.
To unconditionally love is to be indifferent towards what is loved. When people love without conditions, they do it out of a desire for the changes that loving brings about in them, not out of concern or compassion for what is loved. It is no more a virtue for them to do this than any other form of self-stimulation. Unconditional love is fine, but it shouldn’t be done in public.
Be suspicious of the people who present this concept as meritorious! You should no more take their kindly intentions for granted than you should a drug dealer offering a free sample of his wares.