Dirotteremo comes from the verb dirottare, meaning 'to hijack' or 'to divert' (a plane, a ship, etc.). It's a dramatic and less common verb than everyday actions.
In the song, Fedez sings, "So che non hai visto le Hawaii / Dirotteremo Ryanair" (I know you haven't seen Hawaii / We will hijack Ryanair). This line is playful and hyperbolic, suggesting a spontaneous, rebellious act to whisk his love away to a dream destination, making it a memorable and enticing word.
This song is a huge summer hit in Italy, and it's all about that feeling of being completely lost in love. The singers ask, "La vita senza amore dimmi tu che vita è" (A life without love, you tell me what life it is), making it clear that for them, a life without this person is no life at all. The whole song feels like a desperate, exciting journey back to someone they miss, getting lost "dentro al taxi che mi porterà da te" (in the taxi that will take me to you).
It's not just serious and romantic, though. There are these fun, slightly chaotic party scenes mixed in, like going to Oktoberfest and arguing with the DJ. My favorite part is the wild promise, "So che non hai visto le Hawaii / Dirotteremo Ryanair" (I know you haven't seen Hawaii / We'll hijack a Ryanair flight). It's a funny, over-the-top way of saying they'll do anything for the person they love. The song's main idea is that this love is everything, and they'll drop everything else for it: "Chiamami se vuoi / Diglielo agli altri che stasera non puoi" (Call me if you want / Tell the others that you can't tonight).