heterokont

noun

any organism that possesses two flagella of unequal length. Heterokonts include diatoms and some other algae

adjective

possessing two flagella of unequal length

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012