sen·sil·lum (sěn-sĭl'əm) n.
pl.sen·sil·la (-sĭl'ə) A simple sensory receptor consisting of one cell or a few cells, especially a hairlike epithelial cell projecting through the cuticle of arthropods.
[New Latin sēnsillum, diminutive of Latin sēnsus, sense; see sense.]