Linkage criterion in hierarchical clustering in which the distance between two clusters is the distance between those two objects (one from each cluster) that are closest together.
Note: A drawback of this method is the so-called chaining phenomenon, which refers to the gradual growth of a cluster as one element at a time gets added to it. This may lead to impractically heterogeneous clusters and difficulties in defining classes that could usefully subdivide the data.
Source:
PAC, 2016, 88, 407. 'Vocabulary of concepts and terms in chemometrics (IUPAC Recommendations 2016)' on page 432 (https://doi.org/10.1515/pac-2015-0605)