English
longgrass
From long + grass.
Proto-Indo-European *dlongʰos ‘long’
Proto-Germanic *langaz ‘long’
Proto-West Germanic *lang ‘long’
Old English lang ‘long, tall, lasting’
Middle English long
English long
Proto-Indo-European *gʰreh₁- ‘to grow’
Proto-Germanic *grasą
Proto-West Germanic *gras
Old English græs
Middle English gras ‘a grass’
English grass
Today it means
noun Grasses that have been allowed to grow very high or that are from a species that grows very high.
Language periods are conventional ranges, not dates for this word.
Etymograph / longgrass