at·ten·u·ate [ ə ténnyoo àyt ](past and past participleat·ten·u·at·ed, present participleat·ten·u·at·ing, 3rd person present singularat·ten·u·ates)
verb
Definition:
1. transitive and intransitive verb make or become weaker: to reduce the size, strength, or density of something, or become thinner, weaker, or less dense
2. transitive verb make pathogen less virulent: to reduce the virulence of a bacterium or virus, e.g. by exposing it to heat or producing a culture of it in a special medium. Attenuated bacteria or viruses are used in some vaccines.
[Mid-16th century. < Latin attenuat-, past participle of attenuare "make thin" < tenuis "thin"]
