Rachilla

noun

1. The axis of a spikelet of a grass or sedge.
2. In botany, a little rachis; a secondary rachis in a compound inflorescence, as of a spikelet in a grass.
3. Same as rhachilla.
4. The part of a spikelet, in grasses and sedges, that bears the florets
5. A rachis of secondary or higher order in leaves and ferns that are compound more than once.