Same entry in Photius and elsewhere.
[1] The primitive root *ak- means point, and is found with extensions -r-, -m-, -n-. It may in Greek specifically refer to the fire-tempered point of a weapon, esp. in its compound form -hkhs.
[2] This quite different word (a)kh/ B in LSJ) is found only in the accusative, as here. It is interpreted by the Homeric scholia as referring to the silence of courage brought on by adversity (see on Iliad 9.29, 10.218). It is often, as apparently here, related etymologically to a)ke/wn (alpha 831); cf. alpha 867.