11. A computer program product comprising a computer readable storage medium having a computer readable program stored therein, wherein the computer readable program, when executed on a computing device, causes the computing device to implement a natural language content (NLC) disambiguation engine, that operates to: identify, in a corpus of natural language content, a portion of natural language content (NLC) that is determined to be ambiguous with regard to a context of the portion of NLC, thereby identifying an ambiguous content portion; compare the ambiguous content portion to private content information associated with a source of the ambiguous content portion, wherein the private content information is content information accessible to users and resources associated with the source and is not accessible to users or resources that are not associated with the source; identify a domain of the ambiguous content portion based on a domain of a matching portion of the private content information; and perform a clarifying operation that clarifies the ambiguous content portion based on the identified domain of the ambiguous content portion to thereby generate a clarified content portion for processing by a cognitive operation of a cognitive system.
14. The computer program product of claim 11 , wherein the NLC disambiguation engine comparing the ambiguous content portion to private content information comprises: comparing one or more extracted first features of the ambiguous content portion to one or more second features of the private content information; and identifying a matching portion of the private content information based on a degree of correspondence between the one or more extracted first features and the one or more second features, wherein the portion of the private content information comprises a portion having a second feature matching a first feature.