Merriam-Webster Collegiate Dictionary - vocabulary entry

 noun  Date: circa 1934 a word (as the noun book), hyphenated or open compound (as the verb book-match or the noun book review), word element (as the affix pro-), abbreviation (as agt), verbalized symbol (as Na), or term (as man in the street) entered alphabetically in a dictionary for the purpose of definition or identification or expressly included as an inflected form (as the noun mice or the verb saw) or as a derived form (as the noun godlessness or the adverb globally) or related phrase (as one for the book) run on at its base word and usually set in a type (as boldface) readily distinguishable from that of the lightface running text which defines, explains, or identifies the entry