Closely woven lightweight cotton fabric that is used for workwear.
Oz. refers to the ounce weight of the fabric. The more ounces the tougher and more rigid the fabric is.
Raw denim is the unwashed form of the denim fabric that has a very dark look. The denim is much tougher and shrinks more than washed or sanforized denim. Raw denim often has an extra inch or two depending on the weight and type of denim to ensure that the denim shrinks to the right fit. It is recommended that you soak the raw jeans before you start to wear them to ensure the right fit, the best possible wearing experience, as well as even fading.
Small copper "studs" that are used to reinforce the pockets.
Sanforized denim is pre-shrunk denim fabric that has been stretched, shrunk and handled to reduce the shrinkage. The sanforized denim will shrink much less than raw denim and it's thus popular among those who wish to start wearing their jeans directly without soaking them first. Sanforized denim is often slightly softer though often (depending on the denim) retains the same dark hue as raw denim.
Selvedge, selvage or self-edge traditionally refers to denim produced with a shuttle loom. Selvedge or self-edge gets its name from the self finished edge of the fabric where the weaving stops leaving a line that does not fray. Selvedge denim is often more expensive than non-selvedge denim as the denim produced with shuttle loom is only half as wide as the non-selvedge denim. Majority of the vintage denim companies opt for the selvedge denim to retain the vintage denim feeling produced with vintage machines.
Twill refers to fabric woven by passing thread over and then under the warp yarns over and over again to create a diagonal pattern. Denim is a classic example of twill fabric. In the denim industry the two most spoken terms are right and left hand twills. These refer to the weaving direction. For instance, the the right hand twill patterns seem to move upwards and to the right, and vice versa. The right hand twill is more commonly used in comparison to the left.
Warp yarn refers to lengthwise surface yarn through which the filler yarn is woven thus producing the fabric. The warp yarn is usually the dyed yarn that is seen on the surface of the denim. The filler yarn can be seen when the jeans are turned inside out. The filler threads traditionally had a natural cotton color but are now often bleached or dyed for added effect. Non-bleached cotton gives the inside of the denim fabric a yellowish tint.
Creasing that is formed on the front of the jeans, mainly the crotch and thighs. The creasing by the knees is sometimes referred to as knee whiskers. You might also come across references to ass whiskers, which means the creasing/whiskering on the seat of the jeans. The creasing on the back of the knees is sometimes referred to as honeycomb due to the pattern.