The English word 'emotion' is derived from the French word émouvoir. This is based on the Latin emovere, where e-means 'out' and movere means 'move' i.e. emotion means “to move through or out.”
The following are facts an account of emotions' must accommodate.
1. In the paradigm cases; emotions are felt. Furthermore, there is a strong inclination to identify the feeling with the emotion (analogously with: The feeling of a pain is the pain). But unlike pains, emotions are not always felt, being sometimes "subceived" and sometimes wholly beneath consciousness.
2. Emotions are intentional states, and have propositional objects in the sense that what the emotion is about, of, for, at, or to can in principle be specified propositionally.
3. Some emotions have typical physiological concomitants, some of which are to some degree felt; and people are sometimes inclined to identify the feeling of the emotion with the feeling of these changes.
4. Typically an emotion depends on the subject believing some state of affairs to obtain (for example, A would not fear this spider if he didn't believe it likely that the spider is harmful); but this is not always so: Sometimes we experience an emotion despite not believing its propositional con-tent.
5. Some emotions beget dispositions to kinds of actions; so references to such emotions are often a powerful way of explaining actions.
6. Emotions are typically experienced as unified states of mind, rather than as sets of components (for example, a belief + a desire + a physiological perturbation + some behavior).
Or simply, emotion is intense feelings that are directed at someone or something.
Related word with emotions
Feeling: The experiencing of affective and emotional states; "she had a feeling of euphoria"; "he had terrible feelings of guilt"; "I disliked him and the feeling was mutual"
Affect : A broad range of feelings that people experience. "This child impressed me as unusually mature"; "This behavior struck me as odd"
Moods : Are feelings that tend to be less intense than emotions and that lack a contextual stimulus, "he was in a bad humor"
Emotions are different from moods, which are feelings that tend to be less intense than emotions and that lack a contextual stimulus. Emotions are reactions to an object; they are not lasting personality traits. You show your emotions when you are “happy about something, angry at someone, afraid of something.” Moods, on the other hand, are not directed at an object. Emotions can turn into moods when you lose focus on the contextual object.