a. A statement of the meaning of a word, phrase, or term, as in a dictionary entry.
b. A statement or description of the fundamental character or scope of something: "[The panel] calls for a clearer definition of the status of people captured in American military operations" (Economist).
2. The act or process of stating a precise meaning or significance; formulation of a meaning: The definition of terms is essential to any successful scholarly study.
3. The state of being clearly outlined: "With the drizzle, the trees in the little clearing had lost definition" (Anthony Hyde).
4. The level of detail in a recording, production, or digital encoding of an image or sound.
[Middle English diffinicioun, from Old French definition, from Latin dēfīnītiō, dēfīnītiōn-, from dēfīnītus, past participle of dēfīnīre, to define; see DEFINE.]
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2020 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.