The term 'Slight Grimace' can be described as a small facial expression of displeasure or disapproval. It is often referred to as a 'MOUE', which is a French word meaning a small, pouting mouth. A slight grimace is usually a subtle facial expression that conveys a feeling of dissatisfaction or disapproval. It is often used to express disapproval or disapproval of something without having to say it out loud.