A sterile stratum that lies above the stratum being investigated
The rock and subsoil that lies above a mineral deposit such as a coal seam.
To overload or overtax.
A covering for the head; a headdress.
A tier, row, or rank.
A child's apron covering the upper part of the body, and tied with tape or cord; a pinafore. Also tier.
To bore.
To become sleepy or weary.
To make sleepy or weary.
To become bored or impatient (with).