About the title: "Ternary logic" usually means "logic with three truth values". But this piece covers a compiler instruction which handles all binary logic gates with three inputs.
OTOH, it doesn’t matter what assumptions we make, right? Words and phrases often have multiple meanings. The word ternary means composed of three parts, and that fits here.
Ternary comes from the Latin root word ternarius (composed of three things) which contains the root word ter- or tern- which is an adverb variation of the original root terti- meaning 3rd. Same with binary, it comes from the adverb variation bi- or bin- meaning second. Bi- being derived from the original Greek dy- or di-. However, ternary is more correct than trinary because in the binary, we are not using the Latin root for the cardinal two, duo-. We use the adverb version of two, bi-. Trinary just sounds better to some people because tri- and bi- rhyme. For a numerical system composed of four components, we use quarternary which also uses the adverb form of 4, quarter(n)-, instead of the cardinal form, quadr(i)-.
Personal opinion, saying trinary makes you sound like you don't have any formal education.
You’re right; ternary is totally valid and does seem more common now that I look it up. Trinary is a valid synonym, and in the dictionary, and mentioned in the Wikipedia for ternary, and was in fact used by many people during my formal education. Your personal opinion sounds like it’s rather presumptuous, not correct, and designed to start a fight. You have the right to keep it to yourself… or change your mind.
In C, '+' is a binary operator because it accepts two inputs. '?:' is a ternary operator because it accepts three inputs. It is usually referred to as the ternary operator because it is unique in C, but there's nothing fundamental about that.
vpternlogd implements all bitwise ternary operators - those operators that accept three inputs.