Stur or Stair: How To spell?
The word Stur is misspelled against Stair, a noun meaning "A series of steps, as for passing from one story of a house to another; -- commonly used in the plural; but originally used in the singular only."
Word contains consecutive vowels 'AI' in between alphabets st & r is misspelled as 'U'Wrong Spelling:  st-u-r  Correct Spelling:  st-ai-r 
Check more misspelled words of Stair to spell it correct.