'floatable' originates from the word 'float' combined with the suffix '-able', where 'float' meant 'to rest or move on the surface of a liquid without sinking'.

'float' changed from the Old English word 'flotian' and eventually became the modern English word 'float'.

Initially, it meant 'to rest on the surface of water', but over time it evolved into its current meaning of 'capable of floating'.