extimate

Most distant or faraway; outermost, uttermost.

[I]f we could ſee the Soule her ſelf, we could know no more by her then ſhe thus exhibits to our eye: which perſonal figuration in the extimate parts thereof, that repreſent the Body, Face and Veſtments, may be attempered to ſo fine an opacity, that it may reflect the light in more perfect colours then it is from any earthly body, and yet the whole Vehicle be ſo devoid of weight, as it will neceſſarily keep its ſtation in the Aire.

Nor then will this high flight beyond the ſupreme or extimate Heaven ſerve for any evaſion. For as much as we ſpeak of Bodies placed on this ſide of the extimate Heaven, and no Body can be found amongſt Bodies, but it will be circumſcribed by the ambient ſuperficies of the next Bodies about it, that ſuperficies of the ambient Bodies that do immediately compaſs the environ'd Body being its place.

In the works of Jacques Lacan: simultaneously external and intimate.

Since [Edgar Allan] Poe is viewed by the critical tradition as simultaneously inevitable and dubious, we should strive to see him as neither in nor out of the central canon, but rather, to adopt one of [Jacques] Lacan's neologisms, as extimate with relation to it, "simultaneously the intimate kernel and the foreign body," as Mladen Dolar glosses the term succinctly. The extimate is, like the social limit I have been outlining, a fold or fissure within a conceptual and discursive structure, an internal limit.

The romantic ‘fatal desire for mystical union’ emerges as a (non)relation to ‘some other’, to the ‘other’s alien life’[…]. In Lacanian terms this other functions like the extimate Thing, locus of the minimal difference in and more than the subject.