Is the word momento the same in Brazilian and European Portuguese?

Yes

The meaning, spelling, and grammar of the word "momento" are identical in both Brazilian and Continental Portuguese. The only difference is in pronunciation.

In Brazilian Portuguese, the pronunciation is more "syllable-timed," meaning the vowels are more open and clearly articulated. In Continental Portuguese, the pronunciation is more "stress-timed," featuring significant vowel reduction. In Portugal, the unstressed "e" in "momento" is often almost silent or reduced to a very short, neutral sound, and the rhythm is much more clipped.

Brazilian Portuguese Examples

1. "Só um momento, por favor." (Just a moment, please.)
2. "Neste momento, eu não posso falar." (At this moment, I cannot speak.)
3. "Foi um momento muito especial para mim." (It was a very special moment for me.)
4. "Espera um momento aqui, por favor." (Wait a moment here, please.)
5. "Não tenho um momento para perder hoje." (I don't have a moment to lose today.)

Continental Portuguese Examples

1. "Um instante, por favor." (One moment, please.)
2. "Neste instante, não me é possível falar." (At this instant, it is not possible for me to speak.)
3. "Foi um momento muito especial para mim." (It was a very special moment for me.)
4. "Espera um momento aqui, por favor." (Wait a moment here, please.)
5. "Não tenho um momento para perder hoje." (I don't have a moment to lose today.)