dūseti : [dus + e] spoils; pollutes; defames; ill-treats.

A.P. Buddhadatta Mahathera, Concise Pali-English and English-Pali Dictionary [available as digital version from Metta Net, Sri Lanka]

Dūseti [Sk. dūṣayati, caus. of dussati (q. v.). Also as dusseti PvA 82] to spoil, ruin; to injure, hurt; to defile, pollute, defame Vin i.79, 85, 86; iv.212 (maŋ so dūsetukāmo, said by a bhikkhunī), 316 (dūsetuŋ); A iv.169 sq.; J i.454; ii.270; DhA ii.22 (kuṭiŋ, damage, destroy). -- aor. dūsayi J ii.110 (fared ill). -- pp.dūsita. Cp. pa˚, pari˚.

Pali-English Dictionary, TW Rhys Davids, William Stede,