What best defines a "phrase" in language?

A phrase is best defined as a group of words that come together to convey a conceptual unit. This means that even though a phrase does not form a complete thought on its own like a sentence does, it still represents a coherent idea or theme when the words are combined.

For instance, in the phrase "under the weather," the words collectively signify a specific meaning, even though they don’t stand as a complete sentence. Phrases can be part of larger sentences and often function as a single unit within the larger context, playing roles such as subjects, objects, or modifiers. This understanding highlights the significance of phrases in constructing meaningful communication in language.