a. The ability by which one understands; intelligence: concepts that are beyond the understanding of a child.
b. The quality or condition of one who understands; comprehension: Do you have much understanding of calculus? See Synonyms at reason.
2. Individual or specified judgment or outlook; opinion: In my understanding, this is a good plan.
3. A usually implicit agreement between two or more people or groups: an understanding between neighbors over late-night noise.
4. A disposition to appreciate or share the feelings and thoughts of others; sympathy: Can't you show some understanding for the poor child?
Characterized by or having good sense or compassion: an understanding teacher.
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.