Official National Weather Service guidelines say that 'breezy' is when wind velocities are in the 15-25 mph range.
'Windy' is when wind velocities are in the 20-30 mph range.
These wind speeds are the average sustained winds. Wind 'gusts' are when there are bursts of wind higher than the sustained winds. 'Gusty' describes a day when there will be frequent bursts of wind.
