Instil

The verb 'to instil is best spelled like this, with one '-l', in British English. American usage prefers a double '-l', instill. For either , the past forms, instilled, and present participle instilling, have a double '-l-'.

• The noun 'instilment' may be current in American English, but seems to be obsolete in British English, despite its being frequently cited in articles on spelling in other reference works. AWE advises you against its use.

You may also want to see AWE's note on the spelling of the inflections of the verb 'to instil' at -l - -ll-.