Taxonomic history:
   1753: Linnaeus described this species as Panicum compositum in Species Plantarum, 1st ed., p. 57.
   today: The current name for this species is Oplismenus compositus (L.) P. Beauv.

original Latin diagnosis
Panicum spica composita, spiculis linearibus secundis[,] flosculis geminis remotis, calycibus aristatis.

English translation
Panicum with a spike compound; with spikelets linear [and] second; with florets paired; [and] with calyces awned.

English translation with commentary

Panicum	Panicum
with a spike	spica - ablative singular of first declension feminine noun spica, -ae
compound;	composita - ablative singular feminine of perfect passive participle of third conjugation verb compono, componere, composui, compositum; modifies spica
with spikelets	spiculis - ablative plural of first declension feminine noun spicula, -ae
linear	linearibus - ablative plural feminine of group B adjective linearis, -is, -e; modifies spiculis
[and]	[added for smoother reading]
secund;	secundis - ablative plural feminine of group A adjective secundus, -a, -um; modifies spiculis
with florets	flosculis - ablative plural of second declension masculine noun flosculus, flosculi
paired	geminis - ablative plural masculine of group A adjective geminus, -a, -um; modifies flosculis
[and]	[added for smoother reading]
at a distance from one another;	remotis - ablative plural masculine of group A adjective remotus, -a, -um; modifies flosculis
[and]	[added for smoother reading]
with calyces	calycibus - ablative plural of third declension masculine noun calyx, calycis
awned.	aristatis - ablative plural masculine of group A adjective aristatus, -a, -um; modifies calycibus