1.
having few parts; not complex or complicated or involved
a simple problem
simple mechanisms
a simple design
a simple substance
2.
easy and not involved or complicated
a simple game
3.
apart from anything else; without additions or modifications
the simple passage of time was enough
the simple truth
4.
exhibiting childlike simplicity and credulity
5.
lacking mental capacity and devoid of subtlety
6.
(botany) of leaf shapes; of leaves having no divisions or subdivisions
7.
unornamented
a simple country schoolhouse
her black dress--simple to austerity
'simple' - used as a noun
8.
any herbaceous plant having medicinal properties
9.
a person lacking intelligence or common sense
There is an organization called SCROOGE in Charlottesville, Virginia that stands for Society to Curtail Ridiculous, Outrageous, and Ostentatious Gift Exchanges. This was formed to keep gift giving affordable and simple.