Definition

Pencil

Tracing of circular motions on the floor with the toe or inside edge of the working foot, while turning or waiting on the supporting foot. These may vary from small adornments done while marking time to large sweeping arcs which precede the lady as she moves around the man in molinete.

See dibujo, firulete, and rulo

(from batango.com (http://www.batango.com/Loomis.htm))

And that the Lapiz is a sort of squiggle/scribble/circular motion done on the floor with the toe or inside edge of the working foot, while turning or waiting on the supporting foot and needn’t accompany a turn.

(from www.tangocanberra.asn.au (http://www.tangocanberra.asn.au/words.htm#Rulo%20&%20Lapiz))