biclustering

Biclustering, co-clustering, or two-mode clustering^[1] is a data mining technique which allows simultaneous clustering of the rows and columns of a matrix. The term was first introduced by Mirkin^[2] (recently by Cheng and Church^[3] in gene expression analysis), although the technique was originally introduced much earlier^[2] (i.e., by J.A. Hartigan^[4]).
Given a set of m rows in n columns (i.e., an matrix), the biclustering algorithm generates biclusters - a subset of rows which exhibit similar behavior across a subset of columns, or vice versa.

http://en.wikipedia.org/wiki/Biclustering