When talking about aliens people often use the word "civilisation" to mean just "intelligence" and perhaps that's what you're doing because you're thinking abou

When talking about aliens people often use the word "civilisation" to mean just "intelligence" and perhaps that's what you're doing because you're thinking about something that doesn't resemble a human civilisation. I agree with you that an alien intelligence might be very different from a human civilisation. Also, an alien intelligence might not even qualify as a form of life (it might be an artificial intelligence).