Proto-IE: *dhāg-
Meaning: to sharpen
Armenian: daku, pl. gen. dakvach `Axt'
Old Greek: thǟ́gō, thǟgánō, aor. thǟ̂ksai̯ `wetzen, schärfen, anfeuern', thǟgón = oksǘ, ēkonēménon, thē̂ksis = rhopḗ, stigmḗ, tákhos Hsch., thǟgánǟ f. `Wetzstein'
Russ. meaning: точить, острить
References: WP I 822 f