1The construction of a jetty or jetties, especially as a means of protecting a shoreline, river bank, etc.; protection by jetties.
The construction of an upper storey (especially of an early timber-framed building) which projects or juts out beyond a lower load-bearing wall.
Late 18th century. Partly (in early use) from jetty + -ing, and partly (in later use) from jetty + -ing.
Projecting; jutting out.
Early 17th century; earliest use found in Thomas Heywood (c1573–1641), playwright and poet. From jetty + -ing.