Dictionaries, Thesauruses, Pictures, and Press Releases
- Jeffrey, Edward Charles
- Jeffrey, Richard Carl
- Jeffreys, Harold
- Jeffreys, John Gwyn
- Jeffreys-Bullen curves
- Jeffries, Zay
- Jelínek, Jan
- jelly fungus
- jelutong
- Jenkin, Henry Charles Fleeming
- Jenkinson, John Wilfred
- Jensen, Carl Oluf
- Jensen, Johan Ludvig William Valdemar
- Jenynsiidae
- Jepsen, Glenn Lowell
- Jepson, Willis Linn
- jerboa-rat
- Jerne, Niels Kaj
- Jerrard, George Birch
- Jerusalem crickets