Dictionaries
OneLook Dictionaries where you can look up almost 5 million words in over 963 dictionaries.

yourDictionary.com. This site provides access to over 1800 dictionaries in over 250 languages.

Word2Word Language Resources. This site includes links to online dictionaries and translators.

Genealogy Dictionary by Dorothy Stanley. An alphabetical list of genealogy and other useful terms.

Glossaries
Abbreviations Found in Genealogy by Sam Behling. A comprehensive list arranged alphabetically.

FamilySearch Online Glossary relates to all aspects of genealogical research in many countries.

UK Genealogy, Common Acronyms & Jargon by Mark Howells. This is an extremely useful list for anyone researching in the United Kingdom.

Glossar: Die Familie: An Annotated English-German Glossary. This site lists terms related to the family and relatives plus a link to an extensive German genealogical glossary.

Genealogy Quest's Glossary of Terms. This site contains the following glossaries: abbreviations, diseases, epidemics, Latin, occupations and terminology.

Acronym Finder. A searchable database of 35,000+ acronyms/abbreviations and their meanings. The list covers all subjects but focuses on computers, technology, telecommunications and military.

Translators 
Free-Translator.com This easy to use site offers a selection of free dictionaries, translators and language courses for many languages.

Travlang's Translating Dictionaries. Free online translating dictionaries for Afrikaans, Czech, Danish, Dutch, Esperanto, French, Finnish, Frisian, German, Hungarian, Italian, Latin, Norwegian, Polish, Portuguese, Spanish, Swedish and Turkish. The Latin dictionary is useful for old documents.

An Online Translation Service by Altavista. It can handle translations to and from English and Chinese, French, German, Italian, Japanese, Korean, Portuguese and Spanish plus others.

WorldLingo. This site offers free translation of web sites to and from several languages including Chinese, Dutch, English, French, German, Greek, Italian, Japanese, Korean, Portuguese, Russian and Spanish.