The term metallome has been introduced by R.J.P. Williams by analogy with proteome as distribution of free metal ions in every one of cellular compartments. Subsequently, the term metallomics has been coined as the study of metallome. Szpunar  defined metallomics as "comprehensive analysis of the entirety of metal and metalloid species within a cell or tissue type". Therefore, metallomics can be considered a branch of metabolomics, even though the metals are not typically considered as metabolites.
Hiroki Haraguchi gave an alternative definition of "metallomes" as metalloproteins or any other metal-containing biomolecules, and "metallomics" as a study of such biomolecules. In the study of metallomes the transcriptome, proteome and the metabolome will constitute the whole metallome. A study of the metallome is done to arrive at the metallointeractome
The metallotranscriptome  can be ideally defined as the map of the entire transcriptome in the presence of biologically or environmentally relevant concentrations of an essential or toxic metal, respectively metallometabolome would constitute the complete pool of small metabolites in a cell at any given time and this would give rise to the whole metallointeractome and knowledge of this would be of paramount importance in comparative metallomics dealing with toxicity and drug discovery.
- Banci, Lucia; Bertini, Ivano (2013). "Chapter 1. Metallomics and the Cell: Some Definitions and General Comments". In Banci, Lucia. Metallomics and the Cell. Metal Ions in Life Sciences. 12. Springer. doi:10.1007/978-94-007-5561-1_1. ISBN 978-94-007-5560-4. electronic-book ISBN 978-94-007-5561-1 ISSN 1559-0836 electronic-ISSN 1868-0402
- Haraguchi, H. (2004). "Metallomics as integrated biometal science". Journal of Analytical Atomic Spectrometry. 19: 5–14. doi:10.1039/b308213j.
- Mounicou, S.; Szpunar, J.; Lobinski, R. (2009). "Metallomics: the concept and methodology". Chemical Society Reviews. 38 (4): 1119–1138. doi:10.1039/b713633c. PMID 19421584.
- Shanker, A. K.; Djanaguiraman, M.; Venkateswarlu, B. (2009). "Chromium interactions in plants: current status and future strategiesw". Metallomics. 1 (5): 375–383. doi:10.1039/b904571f.
- Szpunar, J. (2005). "Advances in analytical methodology for bioinorganic speciation analysis: metallomics, metalloproteomics and heteroatom-tagged proteomics and metabolomics". The Analyst. 130 (4): 442–465. doi:10.1039/b418265k. PMID 15776152.
- Wackett, L. P.; Dodge, A. G.; Ellis, L. B. M. (2004). "Microbial genomics and the periodic table". Applied and Environmental Microbiology. 70 (2): 647–655. doi:10.1128/AEM.70.2.647-655.2004. PMC . PMID 14766537.
- Williams, R.J.P. (2001). "Chemical selection of elements by cells". Coordination Chemistry Reviews. 216–217: 583–595. doi:10.1016/s0010-8545(00)00398-2.