To Go Through, To Pierce, To Penetrate, To Persist, To Stick To
transitive verb, godan verb
This word consists of kanji with hiragana attached. Because the hiragana ends with an う sound, you know this word is a verb. The kanji itself means pierce, so the verb version is to go through or to pierce.
つらぬく
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: The best way to go through someone's mind or a college campus is to run nude (つらぬ). So if you really want to pierce someone's mind and soul remember this!
父は最後まで自分の信念を貫き通しました。
My father stuck to his beliefs until the end.