scratch and sniff
/ˌskratʃ(ə)n(d)ˈsnɪf/(also scratch 'n' sniff, scratch 'n sniff)
noun
The technique of applying scent to a surface in such a way that it is released when scratched. Frequently attributive: designating something which has or involves scent which is released when scratched.
- A trademark in the United States..
Origin
1960s; earliest use found in Tri-City Herald (Washington). From scratch + and + sniff.