slash

To slash is to cut something with a violent motion, usually using a knife or sword. (verb)

When you use a knife to cut open a package, this is an example of a time when you slash the package.
When a you drop the price from $100 to $1, this is an example of a time when you slash the price.

A slash is a wide or uneven cut or wound, or a short diagonal line, or a streak of color. (noun)

When you have been cut with a knife, the wound is an example of a slash.
A diagonal line between two numbers to express a fraction is an example of a slash.
When a bright streak of blue goes through a yellow painting, this is an example of a slash of blue.

See slash in Webster's New World College Dictionary