Terminology

• Bend Point:   The point of maximum bending on a shaft as measured by a compression test of the shaft on both the tip and butt ends.
   

• Beta-Titanium:  An alloy of Titanium that is harder and denser than typical cast titanium and, therefore, can be forged into drivers with thinner walls.  These thinner walls are as strong or stronger than the club walls found in cast titanium driver heads.  Typically, so-called ‘spring effect’ drivers are forged from Beta-Titanium.
   

• Bounce:  Intentional design condition of the sole angle of an iron head, measured in degrees, in which the trailing edge of the sole is below the leading edge (most often applied to sand wedges and high-lob wedges).  As a rule, the greater the bounce angle, the more the clubhead can cut through tall grass and resist traveling too deeply into sand.  Wedges with less bounce are more effective for run-up shots, especially from normal turf or course sand.
   

• Cavity Back:  The design of an iron head in which the weight is distributed toward the perimeter of the head.  Cavity backs are easily identified as having a recessed area on the back of the head.
   

• Center of Gravity (CG):  The point in a club head at which all of the points of balance intersect.   Generally, a lower center of gravity will produce a higher ball flight and a higher center of gravity will produce a lower ball flight.  Careful, center of gravity is often referred to as the ‘sweet spot’ and that simply is not the case.  (Sweet spot is defined in its alphabetical turn later in this section.)
   

• Coefficient of Restitution (COR):  The amount of energy put into a golf ball as compared to the amount of energy at (after) impact.  The COR is the relation between rebound velocity and initial velocity.  Putty would have a COR of 0.00.  A perfectly elastic material has a COR of 1.00.  (The USGA has established .830 as the highest COR that it will sanction as conforming.)
   

• Deep Face:  A club face that measures higher than average from the sole of the club to the crown.  This is a relative measure; no specific measurement dimension is applied to the term deep face.  Deep face clubs tend to have a higher center of gravity and will tend to launch the ball on a lower trajectory.
   

• Face Angle:   The position of the club face relative to the intended line of ball flight.  A square face angle aligns directly at the target, an open face aligns to the right, while a closed face aligns left.  (Assumes right handed golfers.)
   

• Flex:  The common term given to the relative bending properties of a golf club shaft.  Flex is usually identified by a letter:  L for Ladies, A for Amateur, R for regular, S for Stiff and X for Extra Stiff.
   

• 431 Stainless Steel:  A type of stainless steel used in iron and putter head construction.  In composition, it is not more than 20% carbon, 15-17% chromium, and 1.25-2.5% nickel, with the remainder being iron and a few trace elements.  (For comparison, 421 stainless steel is used in the assembly of automobiles.)
   

• Forged Titanium:  A method of wood head manufacture in which the body and sole of the head is formed (forged) from 100% (pure) titanium.  The face and hosels of such woods are cast from 6-4 ti.  Forged titanium woods are less costly due to their ease of forming as well as their lower raw material cost.
   

• Heel-Toe Weighting:  A type of club head design in which weight is positioned toward the heel and toe of the clubhead in an attempt to stabilize the clubhead (and produce straighter shots) on off-center impacts.
   

• Hybrid:  Any one of a number of golf clubs that maintain characteristics of both a wood and an iron.  Such clubs are often used in place of long irons in a player’s set.
   

• Kick Point:  The point of maximum bending of a shaft as measured by deflecting the tip end while the butt remains stationary.
   

• Launch Angle:  The angle of a ball’s flight immediately after it leaves the club face.
   

• Lie:  The angle between the shaft and the ground line when the club is measured in normal playing position.
   

• Loft:  The angle created as measured from the center of the club face in relation to the hosel bore.  More simply, it is the angle of the club face as related to the shaft position.
   

• Low Profile Head:  An iron or wood head that is smaller from topline to soleline than typical.
   

• Mallet:  A type of putter head identified by its broad appearance from front to back when positioned at address.  The Ram Zebra™ was one of the first popular mallet style putters.
   

• Maraging Steel:  An alloy or family of steels with unique properties.  Typically maraging steels are harder than are non-maraging steels such as 17-4 and 15-5.  Maraging steel is commonly used in club face applications, rather than in entire club heads.
   

• Moment of inertia:  The clubhead heel / toe stability that establishes resistance to twisting of any golf clubhead when that clubhead impacts a golf ball off-center.
   

• OEM (Original Equipment Manufacturer):  A golf club company that, as its main concern, sells completed clubs either on the wholesale level or to the general public.
   

• Offset:  The distance from the forward most point of the hosel to the leading edge of the blade.  Offset will help a player who slices to align the club face with the target, thus reducing the slice.  Offset may also have the effect of producing a higher ball flight.
   

• Perimeter Weighting:  The design concept of redistributing the weight on the head to the heel and toe in an attempt to stabilize the club on all types of impacts.
   

• Progressive Offset:  Iron head design feature in which longer irons have more offset and shorter irons have less.  The offset progresses in somewhat uniform increments through the set.  More offset is featured in long irons as offset tends to eliminate slicing and helps to get the ball airborne, qualities that help most players hit the ball straighter. 
   

• “Rescue”:  A generic name given to any number of clubs that combine features of a wood and an iron.  Most “Rescue” type clubs are designed to take the place of difficult-to-hit long irons.  “Rescue” is also the trademarked name of this type of club from TaylorMade that began the trend toward these clubs.  See also “Hybrid.”
   

• Playability: The combination of all manner of club head design - weight, CG, head shape, etc. – when determining what clubhead design may be favorable to a particular player.  For example, a head that is oversized, has a low CG and exceptional perimeter weighting would have playability characteristics that favor an inconsistent golfer who has trouble getting the ball airborne.
   

• 17-4 Stainless Steel:  A type of stainless steel used in iron head and all metal wood head construction.  In composition, 17-4 is no more than 0.07% carbon, between 15 and 17% chromium, 4% nickel, 2.75% copper, and 75% iron and trace elements.
   

• Shallow Face:  Any wood or iron having a face height less than the norm.  Shallow face clubs typically have lower centers of gravity which makes them an excellent club to make it easier to get the ball airborne.
   

• SP700: A type of beta titanium face used on high-end titanium drivers. SP700 allows the face to be made stronger and thinner, potentially increasing it COR.  (Please note that all  of the beta titanium drivers listed on this website are forged with SP700 as their face material.)
   

• Spring Face: Generic term applied to any titanium driver or driver face, particularly to those whose face is made from a specialized alloy such as SP700, 15-3-3-3, etc.
   

• Spring Effect:  A general term given to the faces of metal woods elated to how much the face compresses and decompresses (springs back) upon ball impact.  The USGA recently established standards for this effect, based upon their assumption that if a face springs more, overall ball distance may be increased, making some of today’s courses obsolete.
   

• Sweet Spot:  The position on the club face at which maximum energy and feel will be transferred.
   

• Toe: The end of the club head most far away from the shaft. Also the term used when a player hits the ball on that area of the club, usually resulting in a shorter shot than desired as well as one going to the right of the intended target, i.e., a "toed" shot (assuming a right-handed golfer.)
   

• Track: The term given to the layout of a golf course; for example, that was a "good" track. Also term given to a putt as it rolls toward the hole; for example, a putt that is heading for the hole is "tracking."
   

• Triple Bogey: A score of three over par on a hole.
   

• Turn: The halfway point of an 18 hole round. A player "makes the turn" after playing #9 and heading to #10 tee.
   

• Up and Down: Also termed "Up and In", the situation in which a player misses the green and then makes one chip and one putt to achieve his score.
   

• Water Hazard: The term applied to any relatively permanent and open area of water (sea, lake, pond, etc.) anywhere on the course. The penalty for hitting your ball into a water hazard is one stroke.
   

• Worm Burner: A poor shot characterized by the ball not getting airborne and simply rolling fast along the ground.
   

• Yardage Marker: An object that indicates how far a specific location id from the hole. Yardage markers are often found at 200, 150, 100 and 50 yard intervals from the green. The markers may be trees or bushes along the sides of the fairway or rough or may be plastic, cement or similar objects sunk in the ground in the center of the fairways.
   

• Yips: The condition, either mental or physical, in which a golfer cannot seem to make short putts, or may not even be able to get them close. A short putt that is missed badly is said to be "yipped."