熨斗とは熨斗鮑(のしあわび）の略称で鮑の肉を薄く剥ぎ、引き延ばして乾かしたもののことで江戸時代以降、古事の贈り物や引き出物に添えられたのが始まりとされています。
鮑を何度も伸ばして使用したことから長寿に続くものとして古くから縁起物とされてきました。熨斗は吉祥文様の一つで、吉祥には幸福や、繁栄、この上なく縁起がいいことなど、おめでたい意味があり、結婚式などにも用いられる定番の柄です。

Traditionally noshi is an thin strip of dried abalone wrapped in folded red and white paper (and attached to a gift to show the regard of the giver)
“Noshi” is an abbreviation for “noshi-awabi (awabi=abalone)”, and is thinly peeled, stretched, and dried abalone meat. It is said to have been served with old-fashioned gifts since the Edo period.
Since the abalone was stretched and used many times, it has long been regarded as a lucky charm for longevity. Noshi is one of the auspicious patterns, and it has auspicious meanings such as happiness, prosperity, and auspiciousness, and is a standard pattern that is also used for weddings and other occasions.

Obi fabrics with this Japanese pattern from the obico selection