(Merely) peculiar hyphenation
You may have found that TeX's famed automatic word-division does not produce the break-points recommended by your dictionary. This may be because TeX is set up for American English, whose rules for word division (as specified, for example, in Webster's Dictionary) are completely different from the British ones (as specified, for example, in the Oxford Dictionaries). This problem is being addressed by the UK TeX User community (see Baskerville, issue 4.4) but an entirely satisfactory solution will take time; the current status is to be found on CTAN (see "using a new language" for instructions on adding this new “language”).
Source: (Merely) peculiar hyphenation