Answer:
A mysterious, fantastic creature, It has one defining feature, And for humans at their worst, In their eyes it's just a horse
It's small but larger than a bee, And agile as a flea. It humms but does not buzz, And it's not covered with fuzz. It is a small collector, Of juicy flower nectar.
A close relative of ketchup that people often spread on their dog.
John Lennon sang about being this toothy creature.
What has a horn but does not work?
What has wheels and flies but is not an aircraft?