The word "most expiable" refers to something that can be atoned for or forgiven. There are several synonyms for this term, including redeemable, forgivable, absolvable, and excusable. "Redeemable" suggests that there is something valuable that can be used to compensate for wrongdoing, while "forgivable" implies that the offense is not too serious and can be excused. "Absolvable" emphasizes the role of absolution or forgiveness in clearing one's sins, while "excusable" suggests that the wrongdoing was committed under extenuating circumstances and can be overlooked. Overall, these synonyms convey the idea that even if one has made a mistake, there is always a chance for forgiveness and redemption.