To become congealed, solidify.
To change from a liquid to solid state, perhaps due to cold; called to freeze in nontechnical usage.
To coagulate, make curdled or semi-solid such as gel or jelly.
To make rigid or immobile.
To become soft or softer
To make something soft or softer.
To palatalize.
To become or make (a consonant) more lenis, to lenite.
To make less harsh
To undermine the morale of someone (often soften up).