Ablutio, ablutiônis, Ipse abluendi actus.Macrob.A washing or rincing away.
Lewis and Short: Latin dictionary
ablūtĭo, ōnis, f. [abluo], a washing, cleansing, Macr. S. 3, 7.—Of baptism, cf. abluo, I. fin. (eccl. Lat.; in Plin. 13, 12, 23, 74, the correct reading is adulatione; v. Sillig ad h. l.).