The word "acher" refers to a feeling of pain or discomfort in the body that can be caused by various reasons. However, there are many other words that can be used as synonyms for "acher" such as throb, sting, soreness, discomfort, and twinge. Throb refers to a rhythmic or pulsating pain that is often associated with a headache or heart condition. Sting is a sharp pain that is sudden and intense, usually caused by an insect bite or a cut. Soreness is a feeling of tenderness or muscular pain that can be caused by physical exertion or injury. Discomfort is a general term that can refer to any kind of physical or emotional discomfort, and a twinge is a sudden sharp pain that lasts only for a moment.