Rasarnavasudhakara 2.481

2.481

atha vīraḥ-
vibhāvair anubhāvaiś ca svocitair vyabhicāribhiḥ |
nītaḥ sadasya-rasyatvam utsāho vīra ucyate ||

Now the heroic sentiment (vīra):
Energy (utsāha), brought to the state of being relished by the audience
by appropriate determinants, consequents, and transitory emotional states, is called the heroic sentiment.