While the form might be interpreted as a diminutive of ur1 (not attested in any other dictionaries), it is also possible to consider it a variant spelling of uré, a word that is otherwise not conclusively attested in Anglo-Norman, but which appears in Continental French (cf. the commentary for ur1). Note, however, Philippe's predilection for otherwise unattested or rare diminutives, particularly at the rhyme e.g.: atomete (Comput ants 2321), bestete (Best ants 1217 and 1305), cuncete (Best ants 3046), lesardete (Best ants ants1306), mustelete (Best ants 1218).
[gdw]