1. noun
    a whole structure (as a building) made up of interconnected or related structures
  2. adjective
    complicated in structure; consisting of interconnected parts; "a complex set of variations based on a simple folk melody"; "a complex mass of diverse laws and customs"
  3. noun
    a compound described in terms of the central atom to which other atoms are bound or coordinated
  4. noun
    a conceptual whole made up of complicated and related parts; "the complex of shopping malls, houses, and roads created a new town"
  5. noun
    (psychoanalysis) a combination of emotions and impulses that have been rejected from awareness but still influence a person``s behavior