fine-tune

from WordNet (r) 3.0 (2006)

fine-tune
    v 1: improve or perfect by pruning or polishing; "refine one's
         style of writing" [syn: {polish}, {refine}, {fine-tune},
         {down}]
    2: adjust finely; "fine-tune the engine" [syn: {fine-tune},
       {tweak}]
    3: make fine adjustments or divide into marked intervals for
       optimal measuring; "calibrate an instrument"; "graduate a
       cylinder" [syn: {calibrate}, {graduate}, {fine-tune}]

from The Collaborative International Dictionary of English v.0.48

fine-tune \fine-tune\ v. t.
   to adjust carefully and precisely so as to achieve optimum
   performance or efficiency; as, The mechanic fine-tuned the
   engine.
   [WordNet 1.5]