The word 'waistband' is correct and usable in written English.
It refers to the strip of fabric or elastic that fits around the waist of a garment, typically pants, shorts, or skirts. Example: "She cinched her waistband tightly, hoping to create a more defined waistline in her dress."
Many schools hope to thwart the decades-long habit of rolling up the waistband of skirts by looking for new styles that can't be "customised".
When the brilliantly normal Sasha and Malia Obama rocked up at the White House "turkey pardoning", they looked exactly as they are: fed-up teenagers dragged to a family event, channelling a bit of safe rebellion via a rolled up waistband.
When arrested and searched, Roberts had £200 cash in her waistband, and a further two bags of cannabis.
There is nothing less stylish than a man terrorised by his own trousers, nothing less attractive than a gut spilling over a too-tight waistband.
A bountiful climate and a weak Australian dollar add the final incentive for anyone, other than an athlete perhaps, travelling to Australia unconcerned about their waistband.
In Miami, he routinely packed a pistol into his waistband to look out for himself.
The department store can discover that your waistband has expanded an inch or so since last year, the airline knows that you usually fly with its main rival, the restaurant remembers that you drink Pinot Grigio.
Below, attached to a set-in waistband, was a full, pleated or gathered skirt.
Many men continue to carry a short, broad, curved, and often highly ornate dagger known as a khanjar (sometimes called a janbiyyah or jambiya), which is worn tucked in the front waistband.
Wrapped around the hips and thighs with one end brought between the legs and tucked into the waistband, the dhoti resembles baggy, knee- length trousers.
Girls' dresses were rather like the easier styles of their mothers at this time, but boys were dressed in a shirt and ankle-length trousers, the waistband of which was buttoned to the shirt.
