"agonising" in the verb sense
1. agonize, agonise
cause to agonize
2. agonize, agonise
suffer agony or anguish
"agonising" in the adjective sense
1. agonizing, agonising, excruciating, harrowing, torturing, torturous, torturesome
extremely painful
Source: WordNet® (An amazing lexical database of English)
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