It depends completely on the context, when referring to any random group of three, then no. However, when referring to God the Father, Son, and Holy Spirit, I believe it should be capitalized. It seems to be grammatically correct, even if it's not, it's good to show respect and clears up any misconception on what you're referring to.
No, coral does not need to be capitalized.
The word evolution does not need to be capitalized.
No, it doesn't need to be capitalized.
No, circa does not need to be capitalized.
No, kinetic energy doesn't need to be capitalized.
The likely word is "trinity" (a group of three). It is capitalized Trinity to refer to the Holy Trinity (three forms of one God) in the Christian faith (Trinitarianism).
No, coral does not need to be capitalized.
The word evolution does not need to be capitalized.
The possible words are:trinity - a group of three (capitalized, the Holy Trinity)trendy - fashionable, modern
No, it shouldn't be capitalized.
No, it doesn't need to be capitalized.
No, circa does not need to be capitalized.
No, kinetic energy doesn't need to be capitalized.
it does not need to be capitilized.
No. Queries do not need to be capitalized.
No, the word "revivalist" does not need to be capitalized unless it is at the beginning of a sentence or part of a proper noun.
No it shouldn't be capitalized.