Gnomon

имя существительное гномон а) столбик-указатель солнечных часов б) древний астрономический инструмент в) геометрическая фигура

Большой англо-русский словарь

Gnomon

noun Etymology: Latin, from Greek gnōmōn interpreter, pointer on a sundial, from gignōskein 1. an object that by the position or length of its shadow serves as an indicator especially of the hour of the day: as a. the pin of a sundial b. a column or shaft erected perpendicular to the horizon 2. the remainder of a parallelogram after the removal of a similar parallelogram containing one of its corners

Энциклопедический словарь Мерриама-Вебстера