Life Science Dictionary -BioTech's Science Dictionary contains over 8300 terms associated with genetics, biochemistry, biotechnology, botany, chemistry, ecology, limnology, pharmacology, toxicology and medicine.

Info-Mine Dictionary -Mining Terms and Definitions including ocean crust, ore, organic, oxide, sandstone, sedimentary, shaft, silt, slate, deposit, diamond, calcium, drill, and more.

Dictionary of Photonics -Terms related to the technology of generating and harnessing light and other forms of radiant energy whose quantum unit is the photon. The science includes light emission, transmission, deflection, amplification and detection by optical components and instruments, lasers and other light sources, fiber optics, electro-optical instrumentation, related hardware and electronics, and sophisticated systems.

Weather Dictionary -There are over 800 weather-related terms, covering the environmental sciences including Alberta clippers, wind, heat, water, celsius, thunderstorms, air, ceiling, visibility, sea level, boiling point, poles, equator, fog, gales, current, sky, clouds, jet stream, climate, tornadoes, hurricanes, blizzards, circulation, westerlies, water vapor, evaporation, humidity, and more.

EPA Terms of Environment -United States Environmental Protection Agency: Terms of Environment includes environmental acronyms, EPA abbreviations, desalination, distillation, pathogens, permeability, pH, marsh, mercury, methane, salinity, sediments, silt, and more.

EqWorld - The World of Mathematical Equations -Algebraic, differential, integral, functional, and other equations.

Dictionary of Units -This provides a summary of most of the units of measurement in use today together with the appropriate conversion factors needed to change them into a 'standard' unit of the S I. Includes meters, kilogram, second, kelvin, mole, hertz, joule, ohm, volt, watt, prefixes, inches, yards, feet, acres, ounces, pints, quarts, liters, gallons, pounds, and more.

Imagine the Universe Dictionary -Terms related to astronomy and astro-physics including angular momentum, black hole, corona, cosmic rays, cosmology, density, eclipse, galactic halo, galaxy, gravity, ions, kelvin, Kepler's Laws, laser, light, matter, microwave, nova, orbit, plasma, pulsar, and more.

Glossary of Energy Terms -Terms related to energy. Entries include laser, latent heat, load, lumen, ballast, biomass, brownout and more.

Bird Dictionary -Terms related to birds and bird care.