The choice of the Merlion as a symbol of Singapore has its roots in history.
In ancient times, Singapore was known as temasek, which is the Javanese word for sea. Temasek was destroyed at the end of the 4th Century A.D. and rediscovered by Prince Nila Utama in the 11th Century. On seeing a strange beast (which he later learnt was a lion) upon his landing, he named the island Singapura, a Sanskrit word for Lion (Singa) and City (Pura).
The Merlion, with its fish-like body riding the waves of the sea, represents the fabled beast that once roamed the island and Singapore's origins as a sea town.