The advent of Halloween in a few days brings to mind the curiously punctuated English term jack-o’-lantern, which is to say Jack of [the] lantern, a fanciful name for, in the definition of the Collins Dictionary, ‘a lantern made from a hollowed pumpkin, which has holes cut in it to represent a human face.’ Curiously, from a language standpoint, jack-o’-lantern had originally come into being as a name for another thing that English describes with a hyphenated phrase having o’ in it, will-o’-the-wisp, i.e. Will of the wisp, which Collins defines as: ‘a pale flame or phosphorescence sometimes seen over marshy ground at night. It is believed to be due to the spontaneous combustion of methane or other hydrocarbons originating from decomposing organic matter.’ You can read a good deal more about jack-o’-lantern and will-o’-the-wisp in a Wikipedia article if you like.
The most common locution in which of has been reduced to o’ is o’clock, literally of [the] clock, which English speakers use in naming the hours. If we go back a great many hours, we find that native English of developed from the Indo-European root *apo-, which meant ‘away, away from, off,’ and in fact off is the native English reflex of that root. (Of is just an unstressed form of off; why did my elementary and secondary schoolteachers never point that out?). The Indo-European root was essentially unchanged in form and meaning in the Greek preposition apo, which appears as a prefix in many technical (and occasionally common) terms, e.g. apogeo/apogee, apoplexia/apoplexy, apóstol/apostle, and apologia/apology. It’s disguised in Spanish afelio, but only slightly shortened in English aphelion.
The Indo-European root *apo- evolved in Latin to ab ‘away, away from, off,’ which died out as an independent word during the early evolution of the Romance languages, largely getting replaced by de. As in the case of Greek apo-, however, we find ab- (or its variant abs-) as a prefix in many compounds that we’ve taken from Latin. A few examples are abdicar/abdicate, abstraer/abstract, aborrecer/abhor, aborto/abort, and absorber/absorb. Ab- might seem to be absent but is merely altered in Spanish ausente, but it’s not absent in English absent.
© 2013 Steven Schwartzman