Manordeifi (Welsh: Maenordeifi) is a parish and community in the hundred of Cilgerran, in the northeast corner of Pembrokeshire, Wales.

In addition to scattered settlement, the parish contains the villages of Abercych and Newchapel (Welsh: Capelnewydd), and many listed buildings and structures.

[5] The Ffynone estate at Boncath belonged at one time to the Morgan family of Blaenbwlan, from which Captain Stephen Colby bought it in 1752.

John Vaughan died in 1919 and, having no sons, left the estate to his daughter Aline Margaret, who had married Captain Cecil John Herbert Spence-Jones, son of the Dean of Gloucester, in 1908; the marriage was a notable occasion, reported in great detail and an occasion for local celebration, despite there being no guests at the wedding and no reception owing to the bride's mother's state of health.

[8] Spence took the additional surname of Colby by royal licence in 1920 and subsequently sold the property in 1927 to a Glamorgan businessman.