The Collaborative International Dictionary of English v.0.48:
Insulate \In"su*late\, v. t. [imp. & p. p. Insulated; p. pr. &
vb. n. Insulating.] [L. insulatus insulated, fr. insula
island. See Isle, and cf. Isolate.]
1. To make an island of. [Obs.] --Pennant.
2. To place in a detached situation, or in a state having no
communication with surrounding objects; to isolate; to
3. (Elec. & Thermotics) To prevent the transfer of
electricity or heat to or from (bodies) by the
interposition of nonconductors.
Insulating stool (Elec.), a stool with legs of glass or
some other nonconductor of electricity, used for
insulating a person or any object placed upon it.