jetty

The journey of 'jetty' begins with the Latin verb 'iacere', meaning 'to throw'. Its frequentative form, 'iactare' (to throw repeatedly or to toss), passed into Old French as 'jeter'. The feminine past participle 'jetee' was used to denote something that is thrown out or projected. In a maritime context, this term was applied to a structure of stones or timber 'thrown out' or projected into the water from the shore. This literal sense of projection perfectly captures the physical form and function of a jetty, which is a man-made projection built to influence water flow or provide a berth.

The word 'jetty' is a simplex form. It entered English from Old French 'jetee' (meaning 'a throw' or 'something thrown out'), which is the feminine past participle of 'jeter' (to throw). The Old French derives from Latin 'iactare', a frequentative form of 'iacere' (to throw).