The Collaborative International Dictionary
Infectiousness
Infectiousness \In*fec"tious*ness\, n. The quality of being infectious.
Wiktionary
infectiousness
n. The state or condition of being infectious.
Usage examples of "infectiousness".
The vigour which Larak exuded was as much a restorative as the infectiousness of his smile.
Killa yawned, catching that infectiousness from Lars, and jammed her arms deeper in the straps, tipping her head back against the padded rim of the tub.