promontorium

Literally "promontory" or "cape", a term used in the names of a small number of features on the Moon where a brighter area protrudes into a darker area. Its use dates from a time when it was believed that the darker features on the Moon were of liquid water; this is now known to be untrue. In recognition of its use over a long period, the term has been retained in certain official names for features on the Moon.