Holer is a term that often refers to a small hole or opening, but there are several synonyms that can be used to describe this type of opening. Some of the most common synonyms for holer are aperture, orifice, puncture, perforation, cavity, crevice, slit, gap, and fissure. Each of these words describes a different type of opening, ranging from small holes to larger gaps or cracks. Whether you are looking to describe a small pinhole or a larger opening, there are plenty of synonyms to choose from that can help you to convey the right meaning and add variety to your writing.