A hip roof, or hipped roof, is a type of roof where all sides slope downwards to the walls, usually with a fairly gentle slope. Thus it is a house with no gables or other vertical sides to the roof. A square hip roof is shaped like a pyramid. Hip roofs on the houses could have two triangular side and two trapezoidal one. A hip roof on a rectangular plan has four faces. They are almost always at the same pitch or slope, which makes them symmetrical about the centerlines. Hip roofs have a consistent level fascia, meaning that a gutter can be fitted all around. Hip roofs often have dormer slanted sides.

Hip roofs are more difficult to construct than a gabled roof, requiring somewhat more complex systems of trusses. Although the roof itself is harder to construct, the walls that carry the roof are easier to build, being all one level. Hip roofs can be constructed on a wide variety of plan shapes. Each ridge is central over the rectangle of building below it. The triangular faces of the roof are called the hip ends, and they are bounded by the hips themselves. The hips sit on an external corner of the building and rise to the ridge. Where the building has an internal corner a valley makes the join between the sloping surfaces. They have the advantage of giving a compact, solid appearance to a structure.

In vertebrate anatomy, hip (or "coxa" in medical terminology) refer to either an anatomical region or a joint.

The hip region is located lateral to the gluteal region (i.e. the buttock), inferior to the iliac crest, and overlying the greater trochanter of the femur, or "thigh bone". In adults, three of the bones of the pelvis have fused into the hip bone which forms part of the hip region.

The hip joint, scientifically referred to as the acetabulofemoral joint (art. coxae), is the joint between the femur and acetabulum of the pelvis and its primary function is to support the weight of the body in both static (e.g. standing) and dynamic (e.g. walking or running) postures. The hip joints are the most important part in retaining balance. The pelvic inclination angle, which is the single most important element of human body posture, is adjusted at the hips.

The five or so tubercles and the lower lateral borders of the sacrum, and the ischial tuberosity ("sitting bone").