Adjective > Contagious

(more contagious; most contagious)

1 : able to be passed from one person or animal to another by touching

a contagious disease

It’s a highly contagious virus.

2 : having a sickness that can be passed to someone else by touching

I have a cold and I’m still contagious.

I’m sick, but the doctor says I’m not contagious.

3 : capable of being easily spread to others : causing other people to feel or act a similar way

She has a contagious smile. (=her smile makes other people smile; her smile makes other people happy)

contagious enthusiasm/laughter

contagiously adverb

a contagiously enthusiastic person

contagiousness noun (noncount)