How to spell SUPREMITY correctly?

If you meant "supremacy", it is spelled with a "c" not a "t". If you meant "supremity" as in extreme or ultimate, it is not a commonly used word and it may be confused with supremecy. More appropriate words could be extremity or ultimacy.

• supremacy The ruler of the kingdom holds absolute supremacy over his subjects.
• supremely The hotel's penthouse suite was supremely luxurious.

Ponnies

• panniers
• pennies
• peonies
• pones
• ponies