Ex, Latin prefix; privative in place of "e" when next letter is a vowel. So Exalate, wingless; Exalbuminous (seed), without albumen, [21].
Excurrent, running out, as when a midrib projects beyond the apex of a leaf, or a trunk is continued to the very top of a tree, [32].
Exiguous, puny.
Exilis, lank or meagre.
Eximius, distinguished for size or beauty.
Exo-, in Greek compounds, outward, as in
Exocarp, outer layer of a pericarp, [120].
Exogenous, outward growing. Exogenous stems, [139].
Exorhizal, radicle in germination not sheathed.
Exostome, the orifice in the outer coat of the ovule.