The Collaborative International Dictionary of English v.0.48:

Engineer \En`gi*neer"\, n. [OE. enginer: cf. OF. engignier, F.
   ing['e]nieur. See Engine, n.]
   1. A person skilled in the principles and practice of any
      branch of engineering; as, a civil engineer; an electronic
      engineer; a chemical engineer. See under Engineering, n.
      [1913 Webster +PJC]

   2. One who manages as engine, particularly a steam engine; an
      engine driver.
      [1913 Webster]

   3. One who carries through an enterprise by skillful or
      artful contrivance; an efficient manager. [Colloq.]
      [1913 Webster]

   Civil engineer, a person skilled in the science of civil
      engineering.

   Military engineer, one who executes engineering works of a
      military nature. See under Engineering.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Engineer \En`gi*neer"\, v. t. [imp. & p. p. Engineered; p. pr.
   & vb. n. Engineering.]
   1. To lay out or construct, as an engineer; to perform the
      work of an engineer on; as, to engineer a road. --J.
      Hamilton.
      [1913 Webster]

   2. To use contrivance and effort for; to guide the course of;
      to manage; as, to engineer a bill through Congress.
      [Colloq.]
      [1913 Webster] Engineer Corps

WordNet (r) 3.0 (2006):

engineer
    n 1: a person who uses scientific knowledge to solve practical
         problems [syn: engineer, applied scientist,
         technologist]
    2: the operator of a railway locomotive [syn: engineer,
       locomotive engineer, railroad engineer, engine driver]
    v 1: design as an engineer; "He engineered the water supply
         project"
    2: plan and direct (a complex undertaking); "he masterminded the
       robbery" [syn: mastermind, engineer, direct,
       organize, organise, orchestrate]