intervacuum
An intervening empty space; a vacant interval.
In the distribution of the Animals themselves, the Subjects and the products of this energy, into the principal Classes, we do not suppose chasms & intervacua or empty Interspaces between the Classes, but ascend from a lower to a higher by an interliminary — and the same principle holds good in the Dynamics of Organic Nature, and the Enumeration and the Order of the three Constitutive Forms of the Vital Energy.
Where it comes from
Formed as inter- + vacuum, but compare the Latin intervacō (“to be empty between”).
Adapted from the Wiktionary entry intervacuum (CC BY-SA 4.0).