ver'y long' base'line interferom"etry
an interferometry technique that enhances angular resolution in the observation of radio signals from distant celestial objects, as quasars, by combining signals from several radio telescopes around the earth or such signals with those from an earth-orbiting satellite. Abbr.: VLBI
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.