Bionanotechnology is the intersection of biology and nanotechnology. Bionanotechnology is a broad and somewhat vague term which is sometimes used interchangeably with nanobiotechnology, which usually refers more specifically to the use of nanotechnological devices for applications in biotechnology.

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Bio-nanotechnology , or nanobiotechnology, a branch of nanotechnology based on using the biological structures such as proteins, ATP's, DNA, etc. As building blocks of nanoscale devices (e.g. Nanomotors). Sometimes called 'wet-dry' technology, where the term 'wet' pertains to biological components and 'dry' to engineered, inorganic nanoparticles. This term should possibly be put in the 'Future' category. Nevertheless, some progress in this area has already been achieved experimentally, and the number of theoretically proposed bio-nanodevices is huge. Speculative and futuristic concepts of bio-nanotechnology are based around so-called 'artificial cells' which would perform better than the 'ordinary' cells e.g. In delivering oxygen, marking and destroying viruses... These ideas are obviously variations of the (bio)nanobot concept.

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Biomolecular Nanotechnology is the term coined for synthetic technology based on the principles and chemical pathways of living organisms, ranging from genetic-engineered microbes to custom-made organic molecules. It encompasses the study, creation, and illumination of the connections between structural molecular biology and molecular nanotechnology, since the development of nano-machinery might be guided by studying the structure and function of the natural nano-machines found in living cells. Bionanotechnology seeks to modify and find technological uses of natural nano-components like the nano-motors of ATP synthase and things like using the scaffold of the enzyme complex of cellulosomes for adding new enzymes to make "nanosomes".

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