TSA CBT Practice Test 2025 - Free TSA CBT Practice Questions and Study Guide

A noun is appropriately defined as a person, place, thing, or idea. This definition encompasses the various categories that nouns can fall under, including concrete entities like "book" (a thing) or "city" (a place), as well as abstract concepts like "freedom" (an idea) or "friendship" (which can describe a relationship between people). By recognizing that nouns represent not just tangible items but also abstract concepts, we understand their fundamental role in language and communication.

The other options describe different parts of speech. For instance, a word that takes the place of a noun refers to pronouns, while a verb form used to modify another verb describes gerunds or participles. Lastly, a conjunction serves to connect clauses, which is another distinct function in sentence structure. Understanding these differences helps to clarify the unique role that nouns play in constructing meaningful sentences.