latronicium

Metathesis of Classical Latin latrōcinium, perhaps influenced by other legal terms ending in -icium, such as iūdicium (“trial, sentence”). Possibly a restructuring based on latrōn- (“thief”) +‎ -icium.

latrōnicium n (genitive latrōniciī or latrōnicī); second declension (Late Latin)

1. robbery, theft, larceny
   • Ca. 500, Lex Salica, Pactus pro tenore pacis dominorum Childeberti et Chlotarii regis :

     Et quia multorum insania convaluerit malis pro inmanitate scelerum digna reddantur. Id ergo decretum est ut apud quemcumque post interdictum latronicium conprobatur vitae incurrat periculum.

     And since criminal excesses have gained in force lately, let the offenders face what is appropriate for the enormity of their deeds. It is therefore decreed that anyone who is proven to have committed larceny after this decree incurs the death penalty.

Second-declension noun (neuter).

¹Found in older Latin (until the Augustan Age).

• Walther von Wartburg (1928–2002) “latrocĭnium”, in Französisches Etymologisches Wörterbuch, volume 5: J L, page 202