progression

UK: /prəʊˈgrɛʃ^ən/ US: /prəˈgrɛʃən/ ,(prə gresh′ən)

WordReference Random House Learner's Dictionary of American English © 2025

pro•gres•sion /prəˈgrɛʃən/   n. 

1. [uncountable] the act of progressing;
   forward or onward movement.
2. [countable] a passing in a series from one member of the series to the next;
   a succession.
3. Mathematics a series of quantities in which there is a uniform relation between each member and the one following it:
   [countable] an arithmetic progression.

See -gress-.

WordReference Random House Unabridged Dictionary of American English © 2025

pro•gres•sion  (prə gresh′ən), n. 

1. the act of progressing;
   forward or onward movement.
2. a passing successively from one member of a series to the next;
   succession;
   sequence.
3. Mathematics a succession of quantities in which there is a constant relation between each member and the one succeeding it. Cf. arithmetic progression, geometric progression, harmonic progression. 
4. Music and Dance the manner in which chords or melodic tones follow one another;
   a succession of chords or tones.
5. Astrology any of a variety of methods of comparing the natal chart to subsequent planetary positions in order to establish an optimum time to accomplish things or to establish the probable time an event occurred or will occur.

• Latin prōgressiōn- (stem of prōgressiō). See progress, -ion
• late Middle English 1400–50

pro•gres′sion•al, adj. 
pro•gres′sion•al•ly, adv. 

Collins Concise English Dictionary © HarperCollins Publishers::

progression / prəˈɡrɛʃən/ noun

1. the act of progressing; advancement
2. the act or an instance of moving from one thing or unit in a sequence to the next
3. a sequence of numbers in which each term differs from the succeeding term by a constant relation
   See also arithmetic progression, geometric progression, harmonic progression
4. movement, esp of a logical kind, from one note to the next (melodic progression) or from one chord to the next (harmonic progression)

proˈgressional adjective