ə̇nˈfektiv adjective
Etymology: Middle English, from Medieval Latin infectivus, from Latin infectus (past participle of inficere to stain, dye, taint, infect) + -ivus -ive — more at infect
1. : producing infection : able to produce infection : infecting
2. : affecting others : infectious
• in·fec·tive·ness noun -es