early 14c., "slab or flat surface for an inscription" (especially the two Mosaic tables of stone), from Old French tablete (13c.), diminutive of table "slab" (see table (n.)). The meaning "lozenge, pill" is first recorded 1580s; that of "pad of writing paper" in 1880.
tablet tab·let (tāb'lĭt)
A small flat pellet of medication to be taken orally.