Webster's Revised Unabridged Dictionary · 1913

Drilling

Drilling , noun

1.
The act of piercing with a drill.
2.
A training by repeated exercises.

Drilling , noun

The act of using a drill in sowing seeds.

Drilling , noun

[German drillich, from Latin trilix having three threads, from the of tres three + licium a thread of the warm. See Three, and compare Twill.]

(Manufacturing) A heavy, twilled fabric of linen or cotton.