Some definitions:

Epigenomics - a cataloging of the affects of reversible, non-genetic changes in genome structure or chromosome organization which influence the patterns of gene expression and, thus, gene function.  Examples of such changes include DNA methylation and modification of histone protein by acetylation, methylation and/or phosphorylation.

Genomics - the genome-wide analysis of the structure and expression of a gene, may include the role of gene structure variation with the level of gene (or its encoded RNA or protein) function.

Metabolomics - the study of complete collection of metabolites present in a cell or tissue under a particular set of conditions (= the metabolome) generating a biochemical profile.  This profile describes the biochemistry defining different physiological states, including disease states, that a cell or tissue may adapt.

Morphomics - the evolutionary, developmental, and comparative study of modular morphology as mediated by gene networks

Nutrigenomics - the study of how constituents of the diet interact with genes, and their products, to alter phenotype and, conversely, how genes and their products metabolise these constituents into nutrients, anti-nutrients, and bioactive compounds

Pharmacogenetics - the study of the role of inheritance in the individual variation in drug response.

Pharmacogenomics - the influence of an individual patients DNA-sequence variation on the effect of a drug.  This includes virtually all genes encoding enzymes that catalyze phase I and II drug metabolism and all genes that encode drug transporters, drug receptors, and other drug targets.

Proteomics - a systematic study of the amounts, modifications, interactions, localization, and functions of all or a subset of proteins at the subcellular, cellular, tissue and whole-organism levels.

Transcriptomics - the characterization of the entire mRNA content of a cell or tissue under specific conditions, and how this transcriptome may change in characteristic ways when the physiological state of the cell or tissue is altered.