It means it's a syntactic unit. In Grammar is a group or set of words that can be synthesized or abbreviated into a single, or that can have the function of a single, within a sentence. Depending on the context, you can take the function of name (noun), verb, adverb , adjective and even preposition . For example the prayer "The sky blue sky lacked clouds". Heaven, is a nominal phrase and can replace in prayer "the sky blue sky" and that in this case, is the subject of prayer.
* Only one "like" per meaning and day, the more "likes" the meaning will appear higher in the list
