ROYAL
ROYALET
ROYALETS
ROYALISE
ROYALISED
ROYALISES
ROYALISING
ROYALISM
ROYALISMS
ROYALIST
ROYALISTIC
ROYALISTS
ROYALIZE
ROYALIZED
ROYALIZES
ROYALIZING
ROYALLER
ROYALLEST
ROYALLY
ROYALMAST
ROYALMASTS
ROYALS
ROYALTIES
ROYALTY
ROYNE
ROYNED
ROYNES
ROYNING
ROYNISH
ROYST
ROYSTED
ROYSTER
ROYSTERED
ROYSTERER
ROYSTERERS
ROYSTERING
ROYSTEROUS
ROYSTERS
ROYSTING
ROYSTS

40 words start with ROY.