Trinidad is the Spanish word for "trinity" — referring to the Holy Trinity in Catholic devotion.
Trinidad is widely used in Spain and Latin America.
Trinidad does not currently appear in the US Social Security Administration's top 1,000 girls' names, so we don't publish a US rank or birth count for it. That says nothing about the name's standing elsewhere in the world — only that it sits outside the ranked US data we rely on.
In Pythagorean numerology the letters of Trinidad reduce to 7, The Seeker. This is a traditional interpretive system, not a factual claim about the name.