This review provides a systematic nomenclature for "Graphene-Family Nanomaterials" (GFNs), including graphene, few-layer graphene (FLG), ultrathin graphene, graphene oxide (GO), reduced graphene oxide (rGO), and graphene nanosheets (GNS). It discusses the unique interactions of GFNs with nucleic acids, lipid bilayers, and small molecule drugs and dyes. The review highlights the potential for GFNs to be either benign or toxic to cells, depending on factors such as layer number, lateral size, stiffness, hydrophobicity, surface functionalization, and dose. GFNs can generate reactive oxygen species (ROS) and interact with membrane lipids, leading to physical or indirect toxicity. Limited in vivo studies suggest systemic biodistribution and biopersistence of GFNs following intravenous delivery, and they may induce foreign body tumors. The review emphasizes the need for comprehensive materials characterization and mechanistic toxicity studies to ensure safer design and manufacturing of GFNs for applications in drug delivery, tissue engineering, and fluorescence-based biomolecular sensing.This review provides a systematic nomenclature for "Graphene-Family Nanomaterials" (GFNs), including graphene, few-layer graphene (FLG), ultrathin graphene, graphene oxide (GO), reduced graphene oxide (rGO), and graphene nanosheets (GNS). It discusses the unique interactions of GFNs with nucleic acids, lipid bilayers, and small molecule drugs and dyes. The review highlights the potential for GFNs to be either benign or toxic to cells, depending on factors such as layer number, lateral size, stiffness, hydrophobicity, surface functionalization, and dose. GFNs can generate reactive oxygen species (ROS) and interact with membrane lipids, leading to physical or indirect toxicity. Limited in vivo studies suggest systemic biodistribution and biopersistence of GFNs following intravenous delivery, and they may induce foreign body tumors. The review emphasizes the need for comprehensive materials characterization and mechanistic toxicity studies to ensure safer design and manufacturing of GFNs for applications in drug delivery, tissue engineering, and fluorescence-based biomolecular sensing.