Full fathom five (catchphrase)

"Full fathom five" is a catchphrase deriving from a verse passage, beginning with those words, in Shakespeare's The Tempest. Its original context, during a storm and shipwreck, is the drowning, in water about 30 feet (five fathoms) deep, of the father of the character to whom the lines are addressed.

Full fathom five thy father lies;
Of his bones are coral made;
Those are pearls that were his eyes:
Nothing of him that doth fade
But doth suffer a sea-change
Into something rich and strange.
Sea-nymphs hourly ring his knell
Hark! Now I hear them – Ding-dong, bell.

This three-word phrase has been repeatedly used in English-language culture, alone or in the context of larger parts or the whole of the passage, or referred to via abridgements of it, over the four centuries since its composition.

...
Wikipedia