High-falutin is a colloquial term used to describe someone or something that is pompous, pretentious or haughty. Synonyms for high-falutin could include terms such as snobbish, superior, conceited, arrogant, self-important, ostentatious or affected. Other synonyms could include words such as grandiose, showy, flamboyant, swollen-headed, vain, narcissistic or boastful. These terms all carry a similar connotation of exaggeration or self-aggrandizement. However, it's important to note that context is key when considering which of these synonyms is most appropriate for your needs, as the impact of each word can vary in different contexts.