Literally, “by the ell of”, the ell being <span class="searchmatch">a</span> unit of measure (often for cloth). IPA(key): /<span class="searchmatch">a</span> l‿on də/ <span class="searchmatch">à</span> <span class="searchmatch">l'aune</span> <span class="searchmatch">de</span> (formal, literary) in the light of, with...
(figuratively) yardstick (standard to which other comparisons are judged) <span class="searchmatch">à</span> <span class="searchmatch">l'aune</span> <span class="searchmatch">de</span> aune inflection of auner: first/third-person singular present indicative/subjunctive...