What does it mean when says the base word for another word?

When someone says "the base word for another word," they are referring to the root word. Here's a breakdown:

* Root word: This is the core, fundamental part of a word that holds its primary meaning. It's the simplest form of the word, without any prefixes or suffixes attached.

* Prefix: This is a word part added to the beginning of a root word, changing its meaning.

* Suffix: This is a word part added to the end of a root word, changing its meaning or grammatical function.

Examples:

* "Happy" is the base word (or root word) for "unhappy" (prefix "un-") and "happiness" (suffix "-ness").

* "Act" is the base word (or root word) for "react" (prefix "re-") and "action" (suffix "-ion").

So, when someone asks for the base word of another word, they're asking you to identify the original, core word before any prefixes or suffixes were added.