This word is recommended for use on a younger sibling of whom smells and looks like a dog. It is a command used as a method of telling someone to rub their face into something, such as food or shite, just as a dog would do.
"dont tellmum coz if u do you must schmecken these" (pointing to nana's cottontails)
Noun: The crystalline residue that forms on the smooth plastic surface of a cellular telephone display by one’s ear during a call. If the display is not wiped off on one’s pant leg after each use, schmear will solidify into the characteristic hardened crystalline coating. Schmear will require the application of a solvent, sometimes saliva, to restore the normal appearance of the display. Also spelled Schm-Ear.
Dude, the schmear on my phone was so bad I had to lick it off to see who was calling.