Japanese WordNet

Current Release & Downloads * Illustrations * References * Links * 日本語 * NICT

We do not maintain Japanese WordNet on this site. Current version of Japanese WordNet is available as follows:


We are aiming to build a large scale, freely available, semantic dictionary of Japanese. As a first step, we have created a WordNet for Japanese, inspired by the Princeton WordNet and the Global WordNet Grid. Basically, you may use, copy, modify and distribute the Japanese WordNet for any purpose without any fee, so long as you keep it under the same license. See the full license for details.

The National Institute of Information and Communications Technology (NICT) started developing the Japanese WordNet in 2006, as part of our support for Natural Language Processing research in Japan. The first version (0.9) was released in February 2009. As the first step in compiling the Japanese WordNet, we added Japanese equivalents to synsets of the Princeton WordNet. In future releases we will add synsets which do not exist in the Princeton WordNet, and modify the structure of the hierarchy, in order to make it better represent the Japanese language.

Please feel free to use the WordNet in any way you please. If you use it for research, please cite one (or more) of our papers. If you have any questions or comments please contact us at: jwordnet@gmail.com. The current Release is Wn-Ja 1.1 All relations (hypernyms, meronyms, ...) come from Princeton WordNet 3.0. We have enriched the synsets with Japanese translations of the definitions and examples as well as lemmas.

Disclaimer: We estimate that this release contains errors in as many as 5% of entries. We decided to spend more effort in increasing the cover than in checking. As we translate the glosses and sense tag text, we expect to fix many of the errors. We also welcome feedback.

Interfaces and Apllications

There are several interfaces available for the Japanese WordNet:

The Japanese Wordnet is used in the following applications:

It is also used in the Japanese edition of Natural Language Processing with Python (Bird, Klein and Loper, 2009) in the section on the Japanese WordNet (12.1.5).


Hitoshi Isahara, Francis Bond, Kyoko Kanzaki, Kiyotaka Uchimoto, Kow Kuroda, Takayuki Kuribayashi, Masao Utiyama, Darren Cook, Asuka Sumida, Kentaro Torisawa
Francis Bond <bond@ieee.org>

Linguistics and Multilingual Studies
Nanyang Technological University
NICT Information Analysis Laboratory
National Institute of Information and Communications Technology