aspect: a grammatical category, usually marked in verbs or verb phrases, that represents the way the parts of a situation (an action or state) are related to each other or to the context. The most common aspects are perfective (also known as completive, which presents a situation as a complete whole), habitual (which presents a situation as being characteristic or repeated), continuous (which presents a situation as occurring before, after, and during some other situation), and imperfective (used without distinction for both habitual and continuous situations). Other aspects are found less commonly, such as punctiliar and repetitive.

Aspect, tense [2] and mood are three important kinds of meanings that many languages' grammatical systems require to be marked inflectionally on verbs, and their markings are often combined with each other. For instance, Spanish has two past "tenses", the difference between which is mostly a difference of aspect. The preterite "dijo" is perfective; it means 'he/she said', referring to a single, complete instance of saying. In contrast, the imperfect "decía" is imperfective. It can also be translated 'he/she said', but refers to the span of time during which the saying went on (without paying any attention to when it began or ended), or to a period of time during which the saying characteristically happened (e.g., many times). Thus, it can also be translated by such things as 'he/she was saying', or 'he/she used to say'. Similarly the preterite "supo" means 'he/she knew' in the sense of coming to know; it can also be translated 'he/she found out, realized', while the imperfect "sabía" 'he/she knew' is the more ordinary kind of continuous knowing (as in 'he/she knew all along'). [Spanish: aspecto]