Noun
An apologist; one who justifies or excuses atrocities by citing extenuating circumstances or positive aspects.
Someone or something that palliates; A person or thing that soothes or reduces difficulties.
(medicine) A medical professional who provides palliative care.
(medicine) A device that allows a patient to control the amount of pain medication that is added into an intravenous drip; infusion pump.
Source: en.wiktionary.org