Many other languages use multiple words to express some of the different concepts that in English are denoted as "love"; one example is the plurality of Greek words for "love" which includes agape and eros.
Although the nature or essence of love is a subject of frequent debate, different aspects of the word can be clarified by determining what isn't love (antonyms of "love").
Interpersonal love refers to love between human beings.
It is a much more potent sentiment than a simple liking for a person.
In recent years, the sciences of psychology, anthropology, neuroscience, and biology have added to the understanding the concept of love.
Helen Fisher, an anthropologist and human behavior researcher, divides the experience of love into three partly overlapping stages: lust, attraction, and attachment.
Some historians date modern conceptions of romantic love to courtly Europe during or after the Middle Ages, although the prior existence of romantic attachments is attested by ancient love poetry.
Recent studies in neuroscience have indicated that as people fall in love, the brain consistently releases a certain set of chemicals, including the neurotransmitter hormones, dopamine, norepinephrine, and serotonin, the same compounds released by amphetamine, stimulating the brain's pleasure center and leading to side effects such as increased heart rate, loss of appetite and sleep, and an intense feeling of excitement.
Research has indicated that this stage generally lasts from one and a half to three years.
As an interpersonal relationship with romantic overtones, love is sometimes contrasted with friendship, although the word love is often applied to close friendships or platonic love.
(Further possible ambiguities come with usages "girlfriend", "boyfriend", "just good friends").