tosyl

 
Pronunciation: /ˈtəʊsʌɪl, -sɪl/

noun

[as modifier] Chemistry
  • of or denoting the toluene-4-sulphonyl radical SO2C6H4CH3, used in organic synthesis: tosyl chloride

Origin:

1930s: from German, from to(luol) and s(ulphon)yl