DuckCorp Dico

Found one definition

1.                 From en.wiktionary.org:
                   
   
   
                   
                     
   [N₂]
   
   ** English
   
   *** Noun
   [en-noun]
   
    1. [en]  The rotational  speed  of the high-pressure  spool  of a two-spool gas turbine  engine  or the intermediate - pressure  spool of a three-spool gas turbine engine, express ed as a percentage  of a certain reference  rotational speed.
    2. * [en]
    3. * [en]
    4. [en] .
   **** Coordinate terms
   
    - [en]
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