progression
1. Maths a sequence of numbers in which each term differs from the succeeding term by a constant relation
2. Music movement, esp of a logical kind, from one note to the next (melodic progression) or from one chord to the next (harmonic progression)
3. Astrology one of several calculations, based on the movement of the planets, from which it is supposed that one can find the expected developments in a person's birth chart and the probable trends of circumstances for a year in his life
Collins Discovery Encyclopedia, 1st edition © HarperCollins Publishers 2005
Progression
A gradual increase in the size or shape of a form or design, keeping the same basic theme or idea.
Illustrated Dictionary of Architecture Copyright © 2012, 2002, 1998 by The McGraw-Hill Companies, Inc. All rights reserved
progression
[prə′gresh·ən] (mathematics)
A sequence or series of mathematical objects or quantities, each entry determined from its predecessors by some algorithm.
(metallurgy)
The fixed dimension between adjacent stations in a progressive die and thus the precise distance the strip must advance between successive cycles of the press.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.