She carefully soaked the rare postage stamps off the envelope and mounted them in her album.

The margin for error in that experiment could be written on the back of a postage stamp, so we had to be extraordinarily careful.

Her handwriting was so tiny it could fit on the back of a postage stamp.

At the trendy brunch spot, they joked about offering yuppie food stamps to customers who ordered avocado toast every day.

Commuters queued to use the ticket stamping machines before entering the platform.

Before boarding, she hurried to the ticket stamping machine to validate her pass.

During the morning rush, the old ticket-stamping machines sometimes jammed, causing long lines at the station.

She found several postage due stamps on the envelopes and had to pay the extra fees.

The museum's exhibit featured rare semi-postal stamps from the early 20th century.

I couldn't find the ticket-stamping machine, so I asked the station attendant for help.