The Collaborative International Dictionary
Custos \Cus"tos\ (k[u^]s"t[o^]s), n.; pl. Custodes (k[u^]s*t[=o]"d[=e]z). [L.] A keeper; a custodian; a superintendent. [Obs.]
Custos rotulorum (r[o^]t`[-u]*l[=o]"r[u^]m) [LL., keeper of the rolls] (Eng. Law), the principal justice of the peace in a county, who is also keeper of the rolls and records of the sessions of the peace.
Wiktionary
n. (context historical English) The main justice of the peace in a given county.
Wikipedia
Custos rotulorum (plural: custodes rotulorum; Latin for "keeper of the rolls") is a civic post which is recognised in the United Kingdom (except Scotland) and in Jamaica.
Usage examples of "custos rotulorum".
Now Admiral the Earl of Blazey spent all his time in retirement at St Kew, happily being the squire, and also the Lord Lieutenant of Cornwall and Custos Rotulorum.