dimethyl sulphoxide
Concise Oxford English Dictionary © 2008 Oxford University Press:
dimethyl sulphoxide /dʌɪˌmiːθʌɪl sʌlˈfɒksʌɪd, -ˌmɛθ-, -θɪl/ (US dimethyl sulfoxide)
▶noun Chemistry a pungent colourless liquid used as a solvent, especially for medicines applied to the skin.
'dimethyl sulphoxide' also found in these Oxford entries:

