The word cosseter means someone who excessively indulges or pampers. There are several synonyms for cosseter, including coddler, spoiler, and indulger. A coddler is someone who treats someone else with excessive care or attention, often in a way that is overprotective or overbearing. A spoiler is someone who gives in to someone else's every demand, often at the expense of other people or relationships. An indulger is someone who allows someone else to do whatever they want without restraint, often leading to negative consequences. These synonyms all describe someone who is overly indulgent and can be used interchangeably with cosseter.