- (a.) Corrupting or tending to corrupt or contaminate; vitiating; demoralizing.
- (a.) Contaminating with illegality; exposing to seizure and forfeiture.
- (a.) Capable of being easily diffused or spread; sympathetic; readily communicated; as, infectious mirth.
- (a.) Having qualities that may infect; communicable or caused by infection; pestilential; epidemic; as, an infectious fever; infectious clothing; infectious air; infectious vices.
Webster's Revised Unabridged Dictionary
| APA | Webster's. (2011). infectious. Retrieved September 22, 2026, from http://smartdefine.org/infectious/definitions/2021339 |
| Chicago | Webster's. 2011. "infectious" http://smartdefine.org/infectious/definitions/2021339 (accessed September 22, 2026). |
| Harvard | Webster's 2011, infectious, Smart Define, viewed 22 September, 2026, <http://smartdefine.org/infectious/definitions/2021339>. |
| MLA | Webster's. "infectious" 27 May 2011. Web. 22 September 2026. <http://smartdefine.org/infectious/definitions/2021339> |