Hunspell is the spell checker of LibreOffice, OpenOffice.org, Mozilla Firefox 3 & Thunderbird, Google Chrome, and it is also used by proprietary software packages, like Mac OS X, InDesign, memoQ, Opera and SDL Trados.
Extended support for language peculiarities; Unicode character encoding, compounding and complex morphology.
Improved suggestion using n-gram similarity, rule and dictionary based pronunciation data.
Morphological analysis, stemming and generation.
Hunspell is based on MySpell and works also with MySpell dictionaries.
C++ library under GPL/LGPL/MPL tri-license.
Interfaces and ports: Enchant (Generic spelling library from the Abiword project), XSpell (Mac OS X port, but Hunspell is part of the OS X from version 10.6 (Snow Leopard), and now it is enough to place the Hunspell dictionary files into ~/Library/Spelling or /Library/Spelling for spell checking), Delphi, Java (JNA, JNI), Perl, .NET, Python, Ruby (, , ), UNO, RichEdit.
Licences: GNU Lesser General Public License and Mozilla Public License.