Etymology: Cognate with or formed similarly to Old Frisian kreftlīk strong, powerful, Middle Dutch crachtelijc strong, powerful, Old High German kraftlīh great, powerful, important, forceful (Middle High German kreftelich ), Old Icelandic krǫptuligr powerful, strong, Old Swedish krapteliker strong, active (Swedish kraftelig ) < the Germanic base of craft n. + the Germanic base of -ly suffix¹. In later use re-formed < craft n. + -ly suffix¹. Compare crafty adj. and later craftily adj.With the semantic development (and the difference in sense to the West Germanic parallels), compare discussion at craft n. Forms with medial vowel. The late Middle English form craftely with medial -e- could alternatively be analysed as showing craftily adj. The Old English semi-encrypted form cræftflkcum in the following example (in a source that sporadically shows deliberate substitution of vowels with consonants immediately following them in the alphabet) is probably to be read as cræftelicum , apparently with epenthetic e to break the consonant cluster tl , although it too could alternatively be interpreted as showing an earlier attestation of craftily adj. (compare discussion at that entry):OE Prudentius Glosses (Boulogne 189) in H. D. Meritt Old Eng. Prudentius Glosses (1959) 14 [Sertaque mystica] dactylico [liga strophio] : cræftflkcum [read cræftelicum].

Etymology: Cognate with or formed similarly to Middle Dutch crachtelīke , craftelīke strongly, by force, Old Saxon kraftlīco powerfully (Middle Low German kreftlīk , krachtlīk ), Old High German kraftlīcho powerfully, strongly, forcefully (Middle High German kreftlich ), Old Icelandic krǫftuliga (also krǫpturligan ) with great force < the Germanic base of craft n. + the Germanic base of -ly suffix². Compare craftly adj.In later use perhaps partly re-formed < craft n. + -ly suffix². The Old English form cræftelice (apparently with epenthetic e to break the consonant cluster tl ) could alternatively, despite its comparatively early attestation (late 9th cent.), reflect a form of craftily adv. with medially reduced -ig- -y suffix¹ (compare similar forms at craftly adj. and discussion at mightly adv.). Compare also the β. forms at craftily adv. and discussion at that entry. For the semantic development (and the difference in sense to the West Germanic parallels), see discussion at craft n. and compare craftly adj. and craftily adv.