influential

The word “influential” means having significant power to affect how things develop or how people think. In plain terms, having a lot of sway or impact over people or events.

“Influential” is pronounced ihnf-luu-EHN-shuhl (/ˌɪnfluˈɛnʃəl/ in IPA).

Here is “influential” used in a sentence: “She became one of the most influential voices in modern architecture.”

“Influential” is an adjective.

The word “influential” comes from Medieval Latin. From Medieval Latin influentialis, built on influentia — see influence.

“Influential” is a fairly common word in modern English, usually learned at around the B2 level.

Powerful describes having direct power or control, while influential describes having the power to affect how things develop or how people think, often indirectly. A writer can be influential without holding any formal power, and an official can be powerful without changing anyone's mind. The two often overlap but are not interchangeable.

Both patterns are correct but work differently. 'Influential in' is followed by an area or process, often an -ing form: 'she was influential in shaping the policy'. 'Influential on' introduces the person or thing affected: 'his work was influential on later designers'.

Important means having great significance or value, while influential specifically means having the power to affect developments or opinions. Something can be important without changing anything — a rare manuscript, for example — whereas an influential book actively shapes how people think or act.