(Botany) (of a compound leaf) having only one pair of leaflets
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
u•nij•u•gate(yuˈnɪdʒ əˌgeɪt, ˌyu nɪˈdʒu gɪt, -geɪt)
(of a pinnate leaf) having only a single pair of leaflets.
[1840–50; < Latin ūnijug(us) having one yoke (ūni- uni- + -jugus, adj. derivative of jugum yoke) + -ate1]
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