Affective means relating to the emotions, or having an effect on them — the feeling side of a person, not the thinking side. Psychologists talk about affective disorders, meaning troubles that sit in mood and feeling, such as a sadness that will not lift. Teachers talk about the affective side of learning: whether a student feels safe, interested, brave enough to try. It is a specialist word. You will meet it in psychology, education, and some medicine, and almost never in the shop or at the dinner table. Though actually, the tidy dictionary line can hide a trap: affective is not a fancy twin of effective. Effective means it works. Affective means it has to do with feeling. They look like family; they are not a pair in use.