Expressions of boredom can be conveyed in a variety of ways, such as sighing, saying 'MEH', or using the interjections 'hohim' and 'hohum'. Sighing is a common expression of boredom, frustration, or disappointment, and is usually accompanied by a deep exhale. 'MEH' is an expression of indifference or apathy, and is often used to indicate that something is not particularly interesting or exciting. 'Hohim' and 'hohum' are both interjections used to express boredom or lack of enthusiasm.