Pedilavium

Part of the church service on Maundy Thursday is the pedilavium.

Source: wiktionary

It is evident […] that the day [Maundy Thursday] was observed, as early as the fifth century, by the solemn celebration of the Lord's supper connected with the ceremony of the washing of feet (pedilavium). Augustin speaks of the celebration of the Lord's supper as being the more ancient and general custom, and of the pedilavium as of later introduction and more partial observance.

Source: wiktionary

Lovefeasts and choir-days were celebrated as covenant festivals, for which all were prepared by being reminded of the covenant of love to Christ and his people, in the speakings, pedilaviums, prostration meetings, and choir homilies (Biertel-Stunden), nor omitting the especial occasions for partaking of the cup of covenant.

Source: wiktionary

Sweeping was like the pedilavium, a purification of the floor of the house and the feet of the believer, contaminated by the insidious flow of a dissipating humanity. In the pedilavium, the feet were washed in the 'bloody Gore' from Christ's Body, and dried by his 'besweated Hair' (FCD [Fulneck Congregation Diaries] 6 August 1755), in an act of purification before the taking of the Lord's Supper.

Source: wiktionary