letter openers

Noun

letter opener (plural letter openers)

1. A device shaped like a fixed-blade knife, usually with a blunt edge; the blunt edge does not slice the envelope so much as precisely tear it.
2. The same sort of device but with a sharpened edge, designed to appeal to customers who enjoy a sharpened one (regardless of whether or not it truly outperforms the nonsharp counterpart).
3. A device incorporating a small razor-style blade in the crotch of a U-shaped plastic handle; it slices the envelope while being, like a safety razor, unlikely to cut the user accidentally.