Geldings are male horses that have been castrated. There are several synonyms used to refer to these horses. For example, they are often called "gelded horses" or simply "gelds". A more informal term is "cut horse". In addition, some people refer to geldings as "neutered horses", although this term is less common. Another term that is sometimes used is "barren horse", although this term can be confusing as it is also used to describe female horses that are unable to reproduce. Overall, while there are several synonyms for the term "geldings", the most commonly used term is still "gelding".