Ardana is one of the Aṣṭottara Sahasranāma (Ashtottara Sahasranama; Thousand and Eight Names) of God Śiva (Siva).The term ‘Ardana’ has come from the dhātu(dhatu; verb-root) ‘ard‘ — that means, to strike, to torture. One who strikes and tortures those who are evilodoers and sinners, and assumes a destructive form to destroy them, is known as Ardana. So Mahādeva  (Mahadeva) is known as Ardana, since he brings retribution upon the sinners. Nīlakaṇṭha (Nilakantha), the commentator, has explained the meaning of the name, as follows —
ardayati janaṃ pāpinaṃ pīḍayati kālāantakarūpeṇetyardanaḥ.