A guide vane for a turbomachine axially pivotably coupled to a radially outwardly disposed flow-limiting wall and to a radially inwardly disposed inner ring of the turbomachine; and a trailing edge gap being formed between an upper trailing edge of the guide vane and the flow-limiting wall and/or between a lower trailing edge of the guide vane and the inner ring; the upper trailing edge and/or the lower trailing edge of the guide vane having at least one air outlet opening for an air outflow for forming an air curtain for at least partially sealing the trailing edge gap in the area of the upper trailing edge and/or the lower trailing edge in the area of the lower trailing edge. Also, a guide vane cascade, as well as a method for manufacturing a guide vane or a guide vane cascade.