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3.01 Introduction

Spelling poses a major problem in English because it is not phonetic and because the rules that can be formulated nearly always have significant exceptions. In addition, there are hundreds of words that have variant spellings in different parts of the English-speaking world, the principal cleavage being between the United Kingdom and the United States. Partly as a result of our historical links with Britain and our proximity to the United States, Canadian spelling has tended to waver between the forms used in these two countries, so that, to this day, there is no clearly established Canadian standard.

While a list of words that have variant spellings in British and American practice would run into the hundreds and still not be exhaustive, the great majority of them fall into a few well-defined classes, as listed below. The British variants are given in the left-hand column, the American in the right-hand column:

  • verbs ending in ise/ize and their derived forms:

    British American
    civilise, civilisation civilize, civilization
    organise, organisation organize, organization
    specialise, specialisation specialize, specialization

  • nouns ending in our/or:

    British American
    colour, honour, favour color, honor, favor

  • nouns ending in re/er:

    British American
    centre, fibre, theatre center, fiber, theater

  • verbs with single l/double l and their derivatives:

    British American
    instil instill
    fulfil, fulfilment fulfill, fulfillment
    enrol, enrolment enroll, enrollment

  • nouns in ce/se1:

    British American
    defence, offence, pretence defense, offense, pretense

  • double l/single l in the past tense of verbs:

    British American
    counselled, labelled counseled, labeled
    travelled traveled

  • treatment of the digraphs ae and oe in words derived from Greek and Latin:

    British American
    anaemia, encyclopaedia anemia, encyclopedia
    diarrhoea, oecumenical diarrhea, ecumenical


  • Back to the note1 British spelling also makes a distinction between certain noun and verb forms that is not maintained in American spelling. Thus, British licence (noun), license (verb) and practice (noun), practise (verb); American license and practice for both forms.

The recommended spelling authority is a reliable Canadian dictionary such as the Canadian Oxford or Gage Canadian Dictionary. It is important to choose one and use it consistently. Both publications are based on research into Canadian usage, contain specifically Canadian terms and reflect the usage of most federal government departments and agencies more closely than do American or British dictionaries. When they list two spellings for a word in the same entry, choose the one entered first. When two spellings are given separate entries, choose the primary spelling, which is the one followed by the definition (the variant simply refers the reader to the primary entry). For scientific and technical words not in Gage or the Canadian Oxford, check Webster’s Third New International Dictionary.

In light of these recommendations, use the following variant spellings: endings in ize, ization, our, re, single l (as in instil) and ce; single l in words such as enrolment; ll in travelled, etc.; and e for digraphs (exceptions: aesthetic and onomatopoeic).


Respect the official spelling of names of U.S. institutions, e.g. Department of Defense, Center for Disease Control.

The rules and lists of words given in this chapter are intended to supplement, not replace the use of the spelling authority you choose. The important point with respect to spelling is to be consistent in your written work unless a good reason exists for using variant or archaic spellings.