Mountd is a past tense verb for the word "mount". It means to climb onto something or to attach onto something. Some synonyms for mountd include ascend, climb, clamber, scale, scramble and hike. These words connote the sense of physical movement, struggle or effort in going up and gaining elevation. Mountd can also suggest the idea of mounting a horse, vehicle or machine. Thus, some related synonyms include ride, board, embark and hitch. In sum, mountd is a versatile verb that can convey different nuances of movement, transportation and action, depending on the context and intended meaning.