not supported.

even the scantiest research would have shown, that proximally and approximately (which was probably meant here) have distinct meanings, and that proximally doesn't mean etwa, ungefähr, or anything like.

Proximally has to do with location. Approximately has to do with estimation, and would be ungefähr, etwa, and ca.

proximal hat ja u.a. auch die anatomische Bedeutung "in Richtung des Rumpfes gelegen". könnte passen?

Agree with odondon. Addi must have misheard "approximately"; "proximally" couldn't be used in the sentence he provided and certainly isn't British slang. "Approximately" does sound a bit like "proximally" when spoken quickly.

BTW it should also be "too" short.

prox•imal /prksIml; NAmE prk/ adj. (anatomy) located towards the centre of the body http://www.oup.com/oald-bin/web_getald7index1a.pl

proximal
(Anatomy) situated nearer to the centre of the body or the point of attachment: "the proximal end of the forearm". The opposite of "distal".
(Geology) relating to or denoting an area close to a centre of a geological process such as ... volcanism.
Oxford Dict. of Eng.

pro|xi|mal <Adj.> [zu lat. proximus= der nächste] (Med.): dem zentralen Teil eines Körpergliedes bzw. der Körpermitte zu gelegen: Die Veränderungen sind im -en Segment des Dickdarms manchmal herdförmig angeordnet (DÄ 47, 1985, 45).
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