A mass of phlegm expelled from the esophagus onto a surface such as asphalt or concrete. It is the only non-shelled mollusk known to man.
While hacking outside Lincoln Center, Charles fathered a land clam on 65th Street
by Suburban Boy May 20, 2004
1 more definition
Noun- Yet another euphemism for vagina.
Harry and I are going out trolling for land-clam.
by Goatboyrising July 27, 2005