This add-on can be installed from the Firefox add-on listing page.
It looks up words by calling dict client on your machine in a subprocess. It can also automatically save words you look up into a list to review later. This extension is for Linux users who use the dict client to look up words. Double click a word on any web page, and the extension will spawn a process to call dict and then display the output in a popup. As an added feature, the words you look up are automatically added to a list for later review.
This addon does not actually implement the DICT protocol, nor call any DICT servers on it's own. It delegates that entirely to the `dict' client on your machine. This extension is quite good and does implement the dict protocol, if that is what you are looking for.
Copyright (C) 2016 Maksim Grinman
This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with this program. If not, see http://www.gnu.org/licenses/.