Merely means "simply, just or only". so it means that YOURS IS ONLY A MOMENT and OURS IS TIMELESSS. it means that being with you is just a moment and SUYIN is timeless. theres a perfect meaning of the YOURS IS MERELY A MOMENT and OURS IS TIMELESS. i'll just tell it to you whats that exactly means [: by the way i'm krizza. nice 2 meet you.