A good rap song might have a catchy hook or infectious beat, but what distinguishes a good rap song from a great rap song is engaging lyrics. Lyrics do more than take up space between beats - they tell a story and allow listeners to personally connect with your work. A good rapper is able to masterfully convey his thoughts and feelings with the right word choices. The more words you know, the better sounding and more original and meaningful word combinations you can create.
Read everything you can get your hands on. Read books, music industry magazines, lyrics to your favorite rap songs and newspapers whenever you can. Reading is one of the easiest and most intuitive ways to expand your vocabulary.
Listen to as many rap songs as possible. There's an old adage among novelists and writers that "writers read." This means that in order to produce your own great works, you need to take in, explore and appreciate the great works of others. Examine lyrics you love, look for words and phrases that seem new to you, take notes on word combinations you like that you would not have thought to use and look up words you might not know.
Take some of the words from your existing rap songs and plug them into an online thesaurus. The thesaurus will produce lists of words with similar meanings. Many of these sites will also let you click on a word to hear how it's pronounced. Start adding these words to your regular rotation and you'll take your vocabulary to the next level.
Take a vocabulary-building class online or from your local community college. If taking a class is not an option, get a vocabulary-building workbook from a bookstore or library and do the exercises daily. Practice your new words both in conversation and in your lyric writing.
Expose yourself to art, people and cultures you don't encounter on a daily basis. Attend lectures or book readings in your community. Strike up conversations with people of diverse backgrounds. Take in as many movies, types of music, live theater events and travel opportunities as you can.
Explore the jargon of hobbies and topics that interest you. Do web searches; take classes or read books about philosophy, social justice movements, politics, sound engineering, art history or medicine. Get involved in one of your passions as a side project to keep your inspirational well full.
Download a pocket dictionary and thesaurus to your smart-phone or keep a hard copy in your pocket. Consider word-a-day apps, emails and calenders.
Make sure you completely understand new words and their associated meanings before you attempt to add them to your lyrics. You don't want to be ridiculed by fans for misusing big words.