90% of the time, speakers of English use just 7,500 words in speech and writing. These words appear in red, and are graded with stars. One-star words are frequent, two-star words are more frequent, and three-star words are the most frequent.
The thesaurus of synonyms and related words is fully integrated into the dictionary. Click on the thesaurus category heading under the button in an entry to see the synonyms and related words for that meaning.
In the US, prom night is especially important to seniors(=students in their last year of high school). They buy expensive prom dresses or rent tuxedos(=formal men's suits), give corsages(=flowers you wear on your dress or jacket) to their dates(=person you ask to go with you to the dance), and sometimes ride to the prom in a rented limo(=very long, expensive car).