seasick

the word 'seasick' is a transparent compound formed from two old english roots. 'sea' originates from proto-germanic saiwiz, referring to a large inland lake or sea, while 'sick' derives from proto-germanic seukaz, meaning 'ill'. the compound directly and logically describes the specific illness induced by the motion of a vessel on the sea. this pattern of combining a noun with 'sick' to denote illness caused by a specific environment or mode of travel (e.g., carsick, airsick) became productive in modern english, with 'seasick' being one of the earliest and most established examples.

Structure: sea + sick sea (old english, meaning 'a large body of salt water', functions as a noun modifier); sick (old english, meaning 'ill, unwell', functions as the core adjective).