The most common term for a displacement of a leg or foot by the partner's leg or foot. Occurs when a dancer places their foot or leg against a leg of their partner and transfers weight to their leg so that it moves into the space of and displaces the partner's leg.
photo (http://www.flickr.com/photos/smoothouse/242417588/)
video sample (http://www.infoimnetz.de/tango/heidelberg/dvd_en.html)
See desplazamiento
(from batango.com (http://www.batango.com/Loomis.htm))
The sacada refers to any move in which one or other partner moves into the space vacated by their partner's leg in such a way that he or she appears to have displaced her or him.
(from layuega.com (http://www.layuega.com/sacada.htm))