Undreading is not a commonly used word, but its spelling can be explained using IPA phonetic transcription. The first syllable is pronounced as "ʌn", which is the schwa sound followed by the letter "n". The second syllable is pronounced as "drɛdɪŋ", with the "dr" sound followed by "ɛd" as in "bed", and then "ɪŋ" as in "sing". So, the word undreading means not feeling fear or anxiety about something that is anticipated, and its spelling reflects its pronunciation.