Definition of "metamorphosis"

With Severne she along doth go, / Her Metamorphosis to show ; / And makes the wand’ring Wy declaim / In honour of the British name.

1612, Michael Drayton, “Poly-Olbion”, in The Complete Works of Michael Drayton, volume I, London: J. R. Smith, published 1876, page 147

I wonder’d at ſuch a Metamorphoſis in ſo ſhort a time, he told me, ’twas for the death of his Wife, that Nature had thus antedated his Years ; ’tis true, that a weighty ſetled ſorrow is of that force, that beſides the contraction of the Spirits, it will work upon the radical moiſture, and dry it up, ſo that the Hair can have no moiſture at the Root.

1626 May 11 (Gregorian calendar), James Howell, “XXVIII. To Mr. R. L. Merchant.”, in Epistolæ Ho-Elianæ. Familiar Letters Domestic and Forren. […], 3rd edition, volume I, London: […] Humphrey Mos[e]ley, […], published 1655, section IV, page 179

Where is the gloriously-decisive change, / Metamorphosis the immeasurable / Of human clay to divine gold, we looked / Should, in some poor sort, justify its price ?

1868, Robert Browning, “The Pope”, in Charlotte Porter, Helen A. Clarke, editors, The Ring and the Book, volume II, New York: T. Y. Crowell & Co., published 1898, lines 1610–3, page 212

The station has been refurbished both at ground level and below ground, where the wide, fluorescently lit platforms are an almost unrecognisable metamorphosis of the dingy, reeking Low Level of old.

1960 December, “The Glasgow Suburban Electrification is opened”, in Trains Illustrated, page 713