What does know mean?
Know is a basic English verb expressing awareness, understanding, certainty, familiarity, and experience. People know facts, people, places, and events; they know how something is done; or they know that a situation is likely to occur. In common usage, knowing a fact is not always the same as understanding its significance, although the verb can express both. "I know her name" reports awareness, while "I know why it happened" indicates understanding. The word also appears in idioms such as "know how," "know better," and "for all I know." Its simplicity makes it useful in everyday speech, formal writing, and expressions of personal knowledge. Although know is highly familiar, its related forms—including known, knowing, knowledge, and unknown—allow speakers to describe what is familiar, what is certain, and what remains beyond their understanding.
verbTo be aware of or have information about something through observation, experience, reasoning, or communication. It can also mean to be certain or to understand fully.
- To have information about something or someone.
- To understand or comprehend something.
- To be certain or confident about something.
- To have personal familiarity with someone.
- To experience or have been present for something.
"She knows the answer to the question."
"I know the answer, but I am not sure how to explain it."
"After many years abroad, she knew the city well."
Knowing is recognizing what is true; understanding is knowing what it means.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does know come from?
Know comes from Old English cnāwan, inherited from Proto-Germanic *knēaną. The word ultimately relates to a Proto-Indo-European root associated with recognizing or coming to know. Related forms across languages include Latin cognoscere, reflected in English cognize and recognize, while the modal can belongs to the same broader root family. The English meaning developed across both the ordinary sense of awareness and the more specialized sense of understanding or experiencing.
Related word forms
How know is actually used
The phrase "know better" often implies that someone has enough information to avoid making a mistaken judgment. The expression "I know" used by itself can mean that the speaker is acknowledging a point, while "Do you know?" is a common way to ask for information.
Easily confused with know
Know is a verb meaning to be aware of or understand something, whereas knowledge is a noun referring to information or understanding acquired.