sdcv was once listed on my recommended technologies page; however, the process of downloading a dictionary for it is time-consuming.
To get a dictionary for sdcv, this excruciating long URL can be used: https://web.archive.org/web/20140917131745/http://abloz.com/huzheng/stardict-dic/dict.org/. This process is made further sluggish by the many user requests to the Internet Archive. There is no guarantee that the site will even be online when needed, as seen from the cyberattacks of May and October 2024.
A better alternative is to download the GNU Collaborative International Dictionary of English.
Once inside the unpacked directory, run the following to change the naming of the files from "CIDE.*" to single letters.
for f in CIDE*; do; mv $f "${f#*.}"; done
Now, the following shell script can be used:
#!/bin/sh letter="$(printf "%.1s" "$*" | tr '[:lower:]' '[:upper:]')" sed -n "/<p><ent>$*<\/ent><br\//I,/^$/p" "/path/to/dictionary/$letter" | w3m -dump -T text/html
The w3m command can be replaced by other command-line web browsers to view the HTML. It takes less than a tenth of a second to return a definition.