The Collaborative International Dictionary of English v.0.48:

Businesslike \Busi"ness*like`\ (b[i^]z"n[e^]s*l[imac]k`), a.
   In the manner of one transacting business wisely and by right
   methods; practical and efficient.
   [1913 Webster]

   2. serious and purposeful.
      [PJC]

WordNet (r) 3.0 (2006):

businesslike
    adj 1: exhibiting methodical and systematic characteristics that
           would be useful in business
    2: not distracted by anything unrelated to the goal [syn:
       businesslike, earnest]

Moby Thesaurus II by Grady Ward, 1.0:

30 Moby Thesaurus words for "businesslike":
   arranged, banausic, breadwinning, commercial, formal, habitual,
   harmonious, in hand, materialistic, methodical, moneymaking,
   normal, ordered, orderly, practical, prosaic, realistic, regular,
   routine, steady, symmetrical, systematic, uniform, usual,
   utilitarian, well-ordered, well-regulated, workaday, workday,
   working