Function: intransitive verb
Etymology: alteration of home in
Date: 1965
: to move toward or focus attention on an objective <looking back for the ball honing in ― George Plimpton> <a missile honing in on its target ― Bob Greene> < hones in on the plights and victories of the common man ― Lisa Russell>
usage The few commentators who have noticed hone in consider it to be a mistake for home in. It may have arisen from home in by the weakening of the \ m \ sound to \ n \ or may perhaps simply be due to the influence of hone. Though it seems to have established itself in American English (and mention in a British usage book suggests it is used in British English too), your use of it especially in writing is likely to be called a mistake. Home in or in figurative use zero in does nicely.