9 letters · 15 points in Scrabble
noun the exponent required to produce a given number
originFrom New Latin logarithmus, term coined by Scottish mathematician John Napier from Ancient Greek λόγος (lógos, “word, reckoning”) and ἀριθμός (arithmós, “number”); compare rational number, from analogous Latin.
Etymology from Wiktionary, CC BY-SA 3.0