rarefiableadj.

1656 tr. T. White Peripateticall Inst. v. 54 Any dense body, that is rarifiable [L. rarificabile].

1680 R. Boyle Exper. & Notes Prodvcibleness Chymicall Princ. ii. 64 in Sceptical Chymist (new ed.) That so inconsiderable a proportion of that liquor, should be rarifiable into so much ardent spirit.

?1722 J. Edwards Thunder in B. Franklin & J. Edwards Select. from their Writings (1920) 234 The parts..instantaneously make their way into the pores of earthly bodies, still burning with a prodigious heat, and so instantly rarifying the rarifiable parts.

1757 J. Rutty Methodical Synopsis Min. Waters 381 That rarefiable air (such as exists in these waters) is not contained in the blood.

1771 H. Pemberton Course Chem. ii. viii. 122 The different substances, of which they are compounded, being some more freely rarifiable than others, are gradually separated from each other.

1804 W. Nicholson tr. A.-F. de Fourcroy Gen. Syst. Chem. Knowl. I. 173 Alcohol, which is liquid, is more rarefiable than water which has much less volatility.

1891 G. Kamensky & A. J. Greenaway tr. D. I. Mendeléeff Princ. Chem. I. ii. 132 If we suppose that gases are rarefiable to a definite limit only..then..the passage of the atmosphere at its upper limits into a homogeneous ethereal medium becomes comprehensible.

1972 R. H. A. Robbins Religio Medici 115 (note) Attenuable, rarefiable.