Stumped? Unveiling the Secret of the Ultra Selfish

The answer to the crossword question ‘Very self-interested is VAIN’ is the word EGOISTIC. The clue suggests that the word we are looking for relates to being self-interested, particularly in an excessive or conceited manner. The term ‘vain’ is synonymous with being egotistical or having a high opinion of oneself. Therefore, ‘egoistic’ fits perfectly as it describes someone who is very self-interested and places their own needs and desires above others, often to an exaggerated extent.