Definition: Distribution of the weight in a clubhead more evenly around the club by moving more weight to the heel, toe and sole. Blades or muscleback irons have most of the weight right behind the center of the clubface. Cavity-back clubs are perimeter weighted, which has the effect of enlarging of making the club more forgiving on off-center hits.
See the FAQ: Why does perimeter weighting make an iron more forgiving?
