Definition and pronunciation
know — verb meaning to be aware of, to be certain about, or to be familiar with a fact, person, or skill.
Pronounced /noʊ/; third person knows /noʊz/; past knew /nuː/; participle known /noʊn/.
Easy explanation
Know means you understand or are sure about something, or you are familiar with someone or a skill. Sometimes, in old or formal writing, know can be a polite way to say have sex (e.g., “know someone in the biblical sense”).
Part of speech and grammar
- Irregular verb: know – knew – known.
- Patterns: know + noun (I know the answer), know + that-clause (I know that you’re right), know + how/where/who… (She knows how to code).
- Stative: rarely used in progressive (I’m knowing ✗), except in set phrases (“You’re knowing, aren’t you?”—nonstandard/jocular).
- Get/come to know = learn over time. Let me know = inform me.
- Derivatives: knowledge, knowledgeable, unknown, well-known, know-how.
Register and tone
Neutral and universal. The sexual euphemism is archaic/biblical, mainly seen in literature, legal quotation, or jokes about “the biblical sense.”
Connection to sexuality
Yes, historically: to know [someone] can mean to have sexual relations with them (“know her in the biblical sense”). This is old-fashioned; modern English prefers have sex, sleep with, or be intimate.
Common collocations
know for sure, know full well, know better (than to), know by heart, know the ropes, know the score, know inside out/know cold, don’t know the first thing about, in the know, let me know, get to know, come to know.
Idioms and set phrases
as you know, for all I know, you know? (discourse tag), not to know someone from Adam (BrE also “from a bar of soap”), know your onions (BrE, be expert), know where you stand, God knows, no one knows, make your presence known.
Prepositions and nuance
- know about = have general information. I know about the policy.
- know of = be aware that something/someone exists. I know of her work.
- know for/as/to (with known): She is known for research; known as a pioneer; known to colleagues.
- know by = recognize via a feature. You’ll know it by the red door.
- know from (informal) = distinguish. He can’t tell right from wrong, let alone know jazz from blues.
- know [someone] in the biblical sense = sexual euphemism.
Word comparisons
- know vs. learn: learn is acquire; know is possess.
- know vs. understand: understand stresses depth/meaning.
- know vs. believe: believe can lack proof; know implies certainty.
- know vs. recognize: recognize is identify from memory.
- sleep with / have sex vs know (biblical): modern neutral vs archaic euphemism.
Real-life examples
- I know the shortcut; turn left after the school.
- Do you know where she lives?
- They got to know each other during training.
- The manual assumes you know basic safety steps.
- The text joked about “knowing” someone in the biblical sense—dated but clear in context.
Sample sentences
- Let me know if the file opens now.
- He knows the poem by heart.
- You should know better than to share passwords.
- I know of her but haven’t met her.
- Older translations say he “knew” her, meaning they had sex.
Synonyms
be aware of, be certain of, understand, grasp, realize, recognize, be acquainted with, be familiar with, comprehend, discern, perceive, identify, be sure of, master, know inside out, have sex with (archaic euphemism sense), sleep with (euphemism), be intimate with (euphemism)
Antonyms
be unaware of, not know, ignore, overlook, misunderstand, misread, mistake, forget, be unfamiliar with, be unsure of
Related terms
knowledge, knowledgeable, know-how, known, unknown, well-known, acquaintance, familiarity, awareness, recognition, certainty, intuition, inference, learn, discover, realize, inform, notify
Notes and etiquette
Use have sex/sleep with instead of the archaic sexual know unless you’re quoting or discussing style. In instruction, prefer tell/let me know (clear request to inform). Avoid progressive knowing except as a deliberate stylistic choice.
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