Ephraim4 Washburn, probably fifth son of (59) Joseph3 Washburn, (43) John2 (5th), (28) John1 (4th); born in ca. 1695 in Bridgewater, Massachusetts Colony, married Mary Polden/Polland, daughter of John and Lydia3 (Tilson) Polden/Polland,  on 13 Jan. 1725/6 in Plymouth, MA.  She was born on 28 Feb. 1706 in Plymouth,  a granddaughter of Ephraim2 and Elizabeth2 (Hoskins) Tilson, of Plymouth. 
Ephraim Washburne bound himself to his cousin, Thomas Washburne Jr., of Bridgewater, to learn the trade of a blacksmith from 6 Nov. 1721 to 20 Mar. 1722/3. Part of the agreement was that Thomas would provide Ephraim with “Meat, Drink, Cloathing, Washing, and Lodging and at the End of his Apprenticeship find him two Compleat Suits of apparrell, one for Common and the other for Special Wear, and allow him a Vice, Bickhorn, Tongs, Hammers, and Sledge and Buttress and Pincers fit for his Work,” but in March 1723/4 Ephraim sued Thomas, claiming that he had failed to perform on part of his agreement, to “find for and allow the said Apprentice the Suit of Cloathing for Special Wear and the said Bickhorn, Tongs, Hammers, Sledge, and Pincers.” Ephraim won the suit for £12 plus court costs because Thomas did not appear in court.  In Sept. 1733 Isaac Churchell of Plympton, husbandman, sued Ephraim Washburne of Plympton, blacksmith, over a £20 bond dated 8 June 1731.  In March 1738/9 Samuel Bradford of Plimton, Gentleman, sued Ephraim Washburne of Plymton over a bond for £60 dated 2 Mar. 1735,  and James Shurtleff of Plymouth, cordwainer, administrator of the estate of Abiel Shurtleff, late of Plymton, carpenter, sued Ephraim Washburn of Plymton, blacksmith, for ejectment from a 16½ acre parcel of land in Plympton which was granted to Abiel Shurtleff in 1707, and passed on to James Shurtleff in 1732 as administrator of the estate of Abiel Shurtleff, stating that in 1733 Washburne “Entred into the Possession of the premisses and without Judgment Disseized the Plaintiff,”  but Washburne countersued, and received judgement for £130 from Shurtleff in Dec. 1741. 
Ephraim Washburn died intestate in 1755 in Plympton, and his eldest son, William Washburn, was appointed as administrator of his estate on 16 July 1755, with Joshua Benson, of Middleborough, and John Bishop, of Wareham, as sureties. His inventory was taken on 25 Sept. 1755 by John Bishop, Ebenezer Briggs, and Joshua Benson, and his estate was divided and distributed on 24 Apr. 1758 to his heirs: his widow Mary Washburn, his eldest son William Washburn, sons Stephen Washburn, Isaac Washburn, Japhet Washburn, and John Washburn, and daughters Lydia Norris, wife of Samuel Norris, Elizabeth Benson, wife of Consider Benson, Marcy Washburn, Phebe Washburn, and Jemima Washburn.  Mary (Polden) Washburn died before 1784.
On 9 Sept. 1784 William Washburn, of Plympton, Consider Benson, Elizabeth Benson, David Vaughan, Phebe Vaughan, and Mercy Washburn, all of Middleborough, and Isaac Washburn, of Rochester, sold to Asa Hunt a meadow in Plympton, being part of four acres our father Ephraim Washburn bought of Nathaniel Thomas, being the meadow set off to our mother Mary Washburn in the division of our said father's estate, excepting 2/11ths which belongs to our brother John Washburn, and the heirs of our late sister Jemima Randell, deceased. 
Ephraim Washburn and Mary Polden had children: