Originally Posted by
Fredd
It's supposedly a
misspelling of the British Brand
Sellotape. It's become a generic word, just as "Scotch tape" is in the US and Canada.
Speaking of generic names and Canada, the word
Aspirin is trademarked there (and in a lot of other countries) by Bayer and many people refer to them generically as
ASA tablets.
Sellotape is a brand and cellotape or cello tape is the product which is a sticky tape made by a depositing a sticky material on a cellophane tape.
Cellotape is definitely not a misspelling.