WOTD

chary (adj): discreetly cautious; hesitant and vigilant about dangers and risks; slow to grant, accept, or expend

I especially like the history of this word I found on Merriam-Webster:

It was sorry that bred the caution of chary.In Middle English, chary meant sorrowful. In a sense switch that demonstrates that love can be both bitter and sweet, chary later came to mean dear or cherished. That's how 16th century English dramatist George Peele used it: 'the chariest and the choicest queen, That ever did delight my royal eyes.' Both sorry and affection have largely faded from chary and in Modern English the word is most often used as a synonym of either 'careful' or 'sparing'