intercurrent

/IH0 N T ER0 K ER1 AH0 N T/
noun
  1. 1

    Something intervening.

adjective
  1. 1

    Running between or among; intervening.

  2. 2

    (of a disease or condition) Simultaneous; occurring at the same time as, or during the period of, another condition.

  3. 3

    (of a disease or condition) Not belonging to any particular season.

Source: https://en.wiktionary.org/wiki/intercurrent