| Elastic energy: | (english) The energy stored in deformed elastic material (e.g., a watch spring). Elastic energy equals where k is the stiffness, and is the associated deflection. Elastic energy is sometimes called elastic potential energy because it can be recovered when the object returns to its original shape; see potential energy. |
| Flexibility: | (english) Flexibility is the inverse of stiffness. When a force is applied to a structure, there is a displacement in the direction of the force; flexibility is the ratio of the displacement divided by the force. High flexibility means that a small load produces a large displacement. |
| Rigid: | (english) An idealized concept meaning something which does not deform under loading. In fact, all objects deform under loading, but in modelling it can be useful to idealize very stiff objects as rigid. |
| Stiffness: | (english) This is a general term which may be applied to materials or structures. When a force is applied to a structure, there is a displacement in the direction of the force; stiffness is the ratio of the force divided by the displacement. High stiffness means that a large force produces a small displacement. When discussing the stiffness of a material, the concept is the same, except that stress substitutes for force, and strain substitutes for displacement; see modulus of elasticity. |
| Retempering | (Concrete Engineering) The addition of water and remixing of concrete which has started to stiffen: usually not allowed as it may affect the ultimate strength. |
| stiffiness | สติฟเนส |
| stiff bristled brush | แปลงขนแข็ง |
| stiffening | เครื่องที่ทำให้แข็ง เช่น ไม้ดาม |
| stiff nut | น้อตหัวแข็ง |
| tail board stiffener | เหล็กรัดฝากะบะท้ายรถ |