The middle finger is the ὁ μέσος and the one next to it is the ὁ παράμεσος, and the pinky is ὁ μικρός.Stephen Hughes in the [url=http://www.ibiblio.org/bgreek/forum/viewtopic.php?f=9&t=2846&p=18760#p18756]Xenophon, The Frugal Estate Manager, Chapter 2[/url] thread wrote:the Greek word for index finger, forefinger is ὁ δείκτης (not listed itself in LSJ if you were thinking to check, but ὁ ἀντίχειρ, "thumb" and ὁ δάκτυλος "finger" or "toe", and ὁ μείζων δάκτυλος "big toe" are).
A joint is an ἄρθρον (cf. ἀρθρῖτις , ιδος, ἡ "gout", but cf. ἄρθρων πόνοι "joint pains"). A knuckle is a κόνδυλος, and to punch (hit with the knuckles) is κονδυλίζειν. The palm is τὸ θέναρ (-αρος), and to slap is τύπτειν as you know. The back of the hand is ὀπισθέναρ. The wrist is the καρπός.
Not relevant to this topic, but just to shoot the breeze, an artery is ἀρτηρία, and a vein is φλέψ, ἡ, (gen. φλεβός), but the aorta is still the ἀορτή.