Low-key and lowkey are idioms with similar meanings, but are different parts of speech. An idiom is a commonly used word, group of words, or phrase that has a figurative meaning that is not easily deduced from its literal definition. Often using descriptive imagery or metaphors, common idioms are words and phrases used in the English language in order to convey a concise idea, and are often spoken or are considered informal or conversational. English idioms can illustrate emotion more quickly than a phrase that has a literal meaning, even when the etymology or origin of the idiomatic expression is lost. An idiom is a metaphorical figure of speech, and it is understood that it is not a use of literal language. Figures of speech like an often-used metaphor have definitions and connotations that go beyond the literal meaning of the words. Mastery of the turn of phrase of an idiom, which may use slang words or other parts of speech common in American slang or British slang, is essential for the English learner. Many English as a Second Language students do not understand idiomatic expressions and idiomatic language such as hit the sack, spill the beans, let the cat out of the bag, silver lining, back to the drawing board, barking up the wrong tree, kick the bucket, hit the nail on the head, face the music, under the weather, piece of cake, when pigs fly, and raining cats and dogs, because they attempt to translate them word for word, which yields only the literal meaning. English phrases that are idioms should not be taken literally. In addition to learning vocabulary and grammar, one must understand the phrasing of the figurative language of idiomatic phrases in order to know English like a native speaker; it is helpful to maintain a list of phrases, common expressions, colloquial terms, and popular expressions to memorize that are used figuratively or idiomatically. We will examine the meaning of the common sayings low-key and lowkey, where they came from, and some examples of their idiomatic usage in sentences.
Low-key is an adjective that describes something that is subdued or quiet, something that is unobtrusive or does not call attention to itself. For instance, a low-key party is one that hosts few attendees, employs quiet music, and encourages small, intimate conversation. The adjective form of the idiom low-key, which is rendered as a hyphenated compound word, came into use sometime in the latter-1800s and is most probably derived from the idea of a quiet, mellow, musical tone.
Lowkey is an adverb that describes doing something in a restrained fashion. For instance, one may say that he lowkey wants to go to the movies. This means that the person in question has a slight desire to go to the movies, but he might be just as happy engaging in a different activity. The adverb form of the idiom lowkey, which is rendered as a closed compound word, came into use about a decade ago and is an example of how language evolves via the internet.