What is the simile of an unicorn?

Unicorns are a symbol of purity.

In Art, the unicorn often represents Christ.

Unicorns can also represent strength and majesty: they are featured on the Royal Arms of both Scotland and the United Kingdom.

Unicorns are often referred to as 'one horned majesty', therefore, the true symbol of a unicorn is its horn. Which varies for the type of unicorn.