No Matter How You Say It: Trustworthiness

Word Origin

Trustworthy is being worthy of trust.  The origin of the word trust is from Middle English < Old Norse traust trust (cognate with German Trost comfort); Can you see how you can be comfortable with something you trust?

From www.dictionary.com

Sign Language

Trust – https://www.handspeak.com/word/search/index.php?id=2270
Mistrustful – https://www.handspeak.com/word/search/index.php?id=4606

Can you see where trust is solid and dependable but mistrust is something you want to keep away from?

Trustworthy Idioms

Fool me once, shame on you.  Fool me twice shame on me.

I wouldn’t trust them as far as I could throw them.

Take my word for it.