Beep the Meep was created in 1980.
Meep meep
That is in the classic cartoon, where he goes Meep Meep!
"Meep" does not appear in a dictionary. However, it is a slang form of onamatopoeia (words that are spelled like sounds, for example, beep, boom, or baaa). According to Wikipedia, it is a form of "beep," so it imitates the sound of a car or bicycle horn. Still, it's in no formal dictionary, so I'd keep it out of your essays.
To Beep or Not to Beep was created on 1963-12-28.
Beep Beep - band - was created in 2001.
Beep Beep - song - was created in 1958.
No Kill No Beep Beep was created on 2000-10-24.
The Beep Seals was created in 2006.
Beep Industries was created in 2000.
Beep - locomotive - was created in 1970.
Let It Beep was created on 2009-09-15.
Beep Prepared was created on November 11th, 1961.