What is "low c"

n. (context music English) the C note exactly two octaves below middle C

"Low C" is a song from British rock band Supergrass' 2005 album, Road to Rouen. It was released on 24 October 2005 as the second single from the album (see 2005 in British music) and peaked at #52 in the UK charts, lasting only the one week in total.