v. dif·fused, dif·fus·ing, dif·fus·es
1. To cause to spread out freely: smoke that is diffused throughout the room.
2. To make known to or cause to be used by large numbers of people; disseminate: diffuses ideas over the internet.
3. To make less brilliant; soften: light that is diffused through frosted glass.
4. To make less intense; weaken: a remark that diffused the tension in the interview.
5. Physics To cause to undergo diffusion.
1. To become widely dispersed; spread out: The hormone diffuses throughout the body.
2. Physics To undergo diffusion.
1. Widely spread or scattered; not concentrated: Diffuse light is often hard to read by.
2. Wordy or unclear: a diffuse description. See Synonyms at wordy.
[From Middle English, dispersed, from Anglo-Norman diffus, from Latin diffūsus, past participle of diffundere, to spread : dis-, out, apart; see DIS- + fundere, to pour; see gheu- in the Appendix of Indo-European roots.]
dif·fusely (-fyslē) adv.
dif·fuseness (-fysnĭs) n.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 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.