sdcv:tldr:3219e

This command is using the program sdcv (StarDict Console Version) to search for a word or phrase defined by ${search_term}. sdcv is a command-line dictionary program that allows you to look up words and their definitions.

The --json flag is used to specify the output format as JSON. Normally, sdcv displays the results in a text-based format, but with this flag, it will provide the results in a structured JSON format instead.

${search_term} is a placeholder for the word or phrase you want to search for. You need to replace it with your desired search term. For example, if you want to search for the definition of the word "apple", you would use:

sdcv --json apple

The --json flag is optional. If you omit it, the command will provide the output in the default text-based format instead of JSON.