As a writer, I rarely need to look up the definition of a word. If I don't know a word, I'm not going to risk using it. However, I frequently check that a word has the exact nuance I want. If it does not, I turn to a thesaurus to search for a closer alternative. Unfortunately, a regular dictionary is next to useless for these purposes. That is why I was pleased to discover dict [1], which not only has the information needed for such purposes, but runs from the command line for added efficiency.

A client for the DICT [2] dictionary network protocol, dict essentially searches several dozen databases and returns comprehensive results in seconds. It is available for major distributions, but note that each database is often in a separate package in distro repositories and must be installed separately from the basic command. The option --dbs (-D) will show a list of these databases, as will the web version [3] of dict (Figure 1). The databases supported by dict include a number of dictionaries, a thesaurus, a collection of acronyms, the Jargon File, the CIA World Factbook, and 34 other languages besides English – far more than the average dictionary offers. The results include not only the range of literal meanings, but numerous contexts as well. Some default results for the word "red" from my current installation are shown in Table 1.

Figure 1: A list of dict's installed databases.

This amount of information makes for intensive scrolling, so dict used with only the basic command and a search term should usually be used with a pager like less or cat. Another option is to specify a specific database so that only the relevant results are given, using the option --database (-d) DATABASE. For instance

dict -d moby-thesaurus red

will return only synonyms (Figure 2). Similarly, if you wanted to look up the Old Testament character Jezebel, you could specify easton to get results only from Easton's Bible Dictionary (1897) (Figure 3) – an encyclopedia entry, rather than a dictionary definition.

Figure 2: A search in a synonym database for synonyms for "red."

Figure 3: A search in a Biblical database for "Jezebel."

Another alternative for limiting results is to choose a strategy from those displayed using the options with --strats (-S). These strategies are analogous to regular expressions, but actually include both basic and modern options (Figure  4). These strategies are not documented, but most are self-explanatory if sometimes a bit obscure. For example, you can specify the prefix, suffix, and substrings to find a family of related words and use soundex to search for similar sounds, which might be useful in a rhymed poem. However, before you choose a limiting strategy, you can use --match (-m) to see how many results a search will return.

Figure 4: Results can be filtered by a choice of strategies.

If a search is not useful, you can trying working more closely with a database. With --serverinfo (-I) and --serverhelp (-H), you can see more information about a database's server. Alternatively, --info DATABASE (-i) displays information about the database itself. However, note that no information may be available for some databases, in which case dict returns the misleading message, invalid database.

Depending on your preferences or how you plan to use search results, you can also use --format (-f) FORMAT. Four different formats are available, as described in the man page: I, S, D, and m. Annoyingly, these formats are diagrammed but not documented, so you may have to do more than one test before finding the one you prefer.

Limitations

Linux has other dictionary tools besides dict. On the desktop, you can choose such applications as GoldenDict, Artha, the WordNet browser, and Gnome Dictionary. However, so far as I can determine, dict is the only one available from the command line and by far the most flexible and thorough. In fact, its potential is so great that its lack of documentation and examples is irksome, if often surmountable. It is not clear whether dict is still being actively developed. Still, with patience, what is available is so useful that no writer on Linux should be without it.