Syntheticaly or Synthetically: How To spell?
The word Syntheticaly is misspelled against Synthetically, an adverb meaning "In a synthetic manner."
Synthetically has double "ll" is mispronounced as "l"Remember double 'LL' in between the strings synthetica & y which should not be misspelled with single 'L'
Wrong Spelling:  synthetica-l-y  Correct Spelling:  synthetica-ll-y 
Find more wrongly spelled words of Synthetically to spell it well.