Origin: Latin prefix sub-
Substring has 3 different meanings across 1 category:
a string that is part of a longer string
"The search function found no matches because the query was not an exact substring of any product code in the database."
A (possibly zero-length) string of characters that is contained in another string.
"The search function found a match because the target keyword appeared as a substring within the longer error message."
To extract a substring from.
"You can simply type the command to extract a substring from that long log file and paste it into your search bar."