From Middle Dutch gêssle, gêsele. The atypical -s-, rather than -z-, points at Old Dutch *gēsl(a), where the -s- was directly followed by the -l-, instead of by a vowel, blocking the s → z sound change, from Proto-Germanic *gaisilaz, from *gaizaz (“spear”) + *-ilaz (suffix deriving names of tools). The loss of the middle syllable was a common change among the Germanic languages, and can also be seen in *karilaz → *karlaz (whence Charles). Cognate with German Geißel.