Vacum or Vacuum: How To spell?
The word Vacum is misspelled against Vacuum, a noun meaning "A space entirely devoid of matter (called also, by way of distinction, absolute vacuum); hence, in a more general sense, a space, as the interior of a closed vessel, which has been exhausted to a high or the highest degree by an air pump or other artificial means; as, water boils at a reduced temperature in a vacuum."
Vacuum has double "uu" is mispronounced as "u"Remember double 'UU' in between the strings vac & m which should not be misspelled with single 'U'
Wrong Spelling:  vac-u-m  Correct Spelling:  vac-uu-m 
Check more misspelled words of Vacuum to spell it correct.