The spelling of the word "most talltalking" is a bit tricky. It is pronounced as /moʊst tɔːltɔːkɪŋ/, with the stress on the second syllable. The word is formed by adding the suffix '-ing' to 'talltalking' which means talking boastfully or exaggerating. 'Most' is used to denote the highest degree or quantity of something. The combination of 'most' and 'talltalking' implies that someone is doing the most boasting or exaggerating. Despite its complexity, the spelling of this word can be mastered with practice.