Taxonomic history:
   1753: Linnaeus described this species as Anthoxanthum odoratum in Species Plantarum, 1st ed., p. 28.
   today: The current name for this species is Anthoxanthum odoratum L.

original Latin diagnosis
Anthoxanthum spica ovato-oblonga, flosculis subpedunculatis arista longioribus.

English translation
Anthoxanthum with a spike ovate-oblong [and] with florets almost pedunculate [and] than the awn longer.

English translation with commentary

Anthoxanthum	Anthoxanthum
with a spike	spica - ablative singular of first declension feminine noun spica, -ae
ovate-oblong;	ovato-oblonga - ovato- (combining form of group A adjective ovatus, -a, -um) + oblonga (ablative singular feminine of group A adjective oblongus, -a, -um); modifies spica
[and]	[modified for smoother reading]
with florets	flosculis - ablative plural of second declension masculine noun flosculus, -i
almost pedunculate	subpedunculatis - ablative plural masculine of group A adjective pedunculatus, -a, -um; modifies flosculis
[and]	[added for smoother reading]
than the awn	arista - ablative singular of first declension feminine noun arista, -ae; modifies foliis
longer.	longioribus - comparative degree, ablative plural masculine of group A adjective longus, -a, -um; modifies flosculis