pinkerton

As a letter s

is the letter s with a.

As a proper noun pinkerton is

for someone from a place of that name near dunbar.

As a noun pinkerton is

(dated|countable) an operative employed by the (1819-1884).

As nouns the difference between pinkerton and mouser

is that pinkerton is (dated|countable) an operative employed by the (1819-1884) while mouser is a cat that catches mice, kept specifically for the purpose.

As a proper noun pinkerton

is for someone from a place of that name near dunbar.