'narrow down' definitions:

Definition of 'narrow down'

(from WordNet)
verb
Define clearly; "I cannot narrow down the rules for this game" [syn: pin down, peg down, nail down, narrow down, narrow, specify]
verb
Become more focus on an area of activity or field of study; "She specializes in Near Eastern history" [syn: specialize, specialise, narrow, narrow down] [ant: branch out, broaden, diversify]