# envelope
## Noun (N)
### Sense: a flat (usually rectangular) container for a letter, thin package, etc.
- ซอง
### Sense: any wrapper or covering
### Sense: a curve that is tangent to each of a family of curves
- โค้งเอนวิโลป
### Sense: a natural covering (as by a fluid)
- สิ่งห่อหุ่มก๊าซ
### Sense: the bag containing the gas in a balloon
- ถุงบรรจุก๊าซ
- ถุงแก๊ส