WordNet sense 1 (any long thin projection that is transient):

knife

WordNet sense 2 (a narrow strip of land that juts out into the sea):

spit

WordNet sense 3 (a human written or spoken language used by a community; opposed to e.g. a computer language):

natural language

WordNet sense 4 (a mobile mass of muscular tissue covered with mucous membrane and located in the oral cavity):

clapper, lingua, glossa