To ascribe something to a person or cause means to say or believe that it comes from them or is caused by them. When a teacher ascribes your improved grades to hard work and focus, she's identifying those qualities as the reason for your success. When historians ascribe the fall of Rome to multiple factors like military weakness and economic problems, they're saying those causes explain what happened.

You can ascribe feelings, actions, qualities, or events to their sources. If you ascribe a friend's bad mood to lack of sleep rather than anger at you, you're identifying what you think is really causing it. Scientists ascribe the extinction of dinosaurs to an asteroid impact. A coach might ascribe a team's victory to excellent preparation.

The word suggests making a judgment about where something comes from or what caused it. Sometimes we ascribe things correctly: you might correctly ascribe your dog's excitement to hearing the word “walk.” But we can also ascribe things incorrectly, like ascribing someone's quietness to disinterest when they're actually just thinking deeply. When we ascribe motives, qualities, or causes to people or events, we're essentially saying “this came from that” or “this person has this quality.” Getting these attributions right requires careful observation and honest thinking about what really causes what.