rotten borough

A parliamentary borough retaining representation despite a greatly diminished electorate. Some had very few voters; Old Sarum had no resident electorate. Vulnerable to bribery and patronage, they became a major target of reform. The Reform Act 1832 disfranchised 56 such boroughs and reduced 30 others. Unlike a pocket borough, a rotten borough was defined by its small electorate rather than control by a patron.