transitive. To make less thick, dense, or viscid; to dilute. Also figurative.

transitive. To lower in quality, quantity, or strength, relax; to thin (the blood); to shorten (life); to alleviate (pain). Obsolete.

transitive. To make (esp. air) thin, usually by expansion; to make looser or less dense in texture. Also intransitive: †to bring about rarefaction…

transitive. = subtilize, v. 3. Cf. earlier subtle, v. 3.

transitive. = subtilize, v. 3. Occasionally also intransitive. Cf. earlier subtile, v. 1, subtle, v. 3a.

To thin out in consistency, render less dense.

To subtilize, refine, rarify.

To subtilize.

To make thin in consistency, to separate the particles of a substance, to diminish density, rarefy.

transitive. To make (a substance) more fluid or volatile; to make thinner, to rarefy. Also: to refine. Occasionally with into. Also intransitive. Now…

transitive. To make thin; = thin, v.1 5.