Stretch fabric
Stretch fabric is a synthetic fabric which stretches. Stretch fabrics are either 2-way stretch or 4-way stretch.
2-way stretch fabrics stretch in one direction, usually from selvedge to selvedge (but can be in other directions depending on the knit). 4-way stretch fabrics, such as spandex, stretches in both directions, crosswise and lengthwise. Stretch fabrics evolved from the scientific effort to make fibres using neoprene. From this research, in 1958 commercial stretch fabrics ('elastomerics') such as spandex or elastane (widely branded as 'Lycra') were brought to the market.