Government official at the local level under the authority of a prefect
A subprefect is a senior government official in several countries at the local level, such as Brazil and France.
Brazil
In Brazil, a subprefect (subprefeito) is the highest official of a subprefecture, which is a subdivision of certain large municipalities (São Paulo, Rio de Janeiro). The subprefect serves under the municipality's prefect (prefeito).