AmericanLiterature.com: Gives the meaning of a single word everyday, and links to an archive of previously listed words. Also includes a daily random quote.
Dictionary.com : Word of the Day: Features the meaning of a single random word, its pronunciation, etymology and examples of word usage. Includes a daily word mailing list.
German Word of the Day: Learn German words with meanings and pronunciations.
Hebrew - Word of the Day: Offers mailing list two or three times per week featuring modern day and biblical Hebrew words. Provides information on subscribing.
Italian Word of the Day: Features a new word every day spoken in Italian by a native speaker and a phrase using the word in an example. Includes translation in English.
Merriam-Webster's Word of the Day: A searchable dictionary and thesaurus. Includes word games, daily word with its meaning, history, usage in sentences, and etymology.
Mot du Jour - French Word of the Day: Provides a new French word emailed daily with pronunciation, example of usage, and related words. Includes archive of previous French words, and subscription information.
NCES Students' Classroom: Provides meaning of a word daily from Webster's dictionary.
Oxford English Dictionary : Daily Word: Features a daily word with its meaning, pronunciation, spelling, etymology, and date chart.
Ransford.org Word of the Day: Features a mailing list, with daily post of a new word.
Travlang's Words for Travellers: Includes a daily English word and its translation in many other languages.
Vocabulary List: A free mailing list which features the meaning and pronunciation of a different word daily.
Word of the Day: Lists the meaning of the word and etymology from three different dictionaries.
Word of the Day - Spanish Language: Contains a word from the Spanish vocabulary each day of the month.
Word of The Day by WordThink: WordThink's Word of The Day provides unpretentious words that are insightful and persuasive.
Wordsmith.org: Features a daily word with its meaning, etymology, usage and pronunciation. Also offers anagrams, acronyms, dictionary and thesaurus by email.
Worthless Word for the Day: Features the meaning and usage examples of an obscure word everyday. Provides an archive of previously featured words.