What does Sahasrara mean and why is it called the thousand-petalled lotus?

Sahasrara is a Sanskrit compound of sahasra (thousand) and ara (spoke or petal). It is called the thousand-petalled lotus because its classical symbolic representation is a lotus with one thousand petals radiating in all directions — an image of infinite, unlimited consciousness. The number one thousand in the Indian tradition means infinity rather than a specific count. Each petal bears one letter of the Sanskrit alphabet repeated cyclically, signifying that this chakra contains the totality of all knowledge and all expression. The lotus blazes like a thousand suns, radiating all colours simultaneously — an image for consciousness that is not defined by any particular quality but includes all within its infinite nature.