sleighly

• sleiȝliche, sleeiȝli, slily, sleȝly, sliȝly, slyȝly, slyliche, sclely, slely, sliliche, slilyche, slighliche, sleili, sclyly, sleyghly, sleghely, slighly, sleghli, slahliche, sleeili, sleeiȝly, slyly, slili, sleigly, sclyȝly, slyghly, sleȝlych, sleiliche, sleilich, slehliche

From sly +‎ -ly.

• IPA^(key): /ˈsliːliː/, /ˈslɛi̯liː/, /ˈslixliː/, /ˈslɛi̯xliː/, /-liːtʃ(ə)/

sleighly

1. Judiciously, consideredly, shrewdly; in a wise way.
2. Adeptly, expertly, in an expert or skilled way.
   • 1470–1485 (date produced), Thomas Malory, “(please specify the chapter)”, in [Le Morte Darthur], book V, [London: […] by William Caxton], published 31 July 1485, →OCLC; republished as H[einrich] Oskar Sommer, editor, Le Morte Darthur […], London: David Nutt, […], 1889, →OCLC:

     He wolde nat abyde uppon no poure man for no maner of thyng—and ever he slow slyly and slypped to another, tylle all were slayne to the numbir of a hondred thousand

     He wouldn't wait for any poor man for anything; and he always slayed (his enemies) skillfully then quietly moved on to the next one, until all 100,000 of them had been killed.

3. Attentively; with care, attention or discernment.
4. Slyly, artfully; intelligently and using deception.
5. Without being noticed or detected; covertly.

• English: slyly, slily
• Scots: sleely, sleelie

• “sleighlī, adv.”, in MED Online, Ann Arbor, Mich.: University of Michigan, 2007, retrieved 2019-06-05.