The word Collbourn is spelled with two L's, even though it may initially appear as if there should only be one. This is because the second L is what is known as a doubled consonant, which serves to indicate a short vowel sound in the syllable that precedes it. In IPA phonetic transcription, Collbourn would be spelled /ˈkɒlbɔːn/, with the symbol "ː" indicating the doubling of the consonant. It is important to pay attention to the placement of doubled consonants in order to spell words correctly.