Quenya 

hasa-

verb. to treat (medically), (help to) cure; to treat kindly, make easy

A verb in notes from 1969 given as haþa- and translated “treat kindly/make easy, (help to) cure” or just “treat (medically)”, derived from the root √HATH (PE22/166 notes #109-110). After þ > s in Quenya, it would be pronounced hasa-.