Since this word consists of a kanji with hiragana attached, you can bet that it will use the kun'yomi reading. You didn't learn that reading with this kanji, so here's a mnemonic to help you:
You're trying not to say it directly, but trying to figure out how to express something. That something is that you are a wuss (あらわす). Sorry, had to be expressed.
But it’s not okay to express your discomfort so bluntly.
All citizens are expressing some dissatisfaction with the high tax.
I can’t begin to express how good this apple cinnamon whiskey is.