FROM STRONG’S GREEK DICTIONARY (1890)

Strong’s Greek Dictionary (1890) — public domain, printed whole.

eutonos εὐτόνως — yoo-ton'-oce — adverb from a compound of 2095 and a derivative of teino (to stretch); in a well-strung manner, i.e. (figuratively) intensely (in a good sense, cogently; in a bad one, fiercely):--mightily, vehemently.

see GREEK for 2095