Middle English
ayen, ayein, ayan, ageyn, again "back, in the opposite direction, to a former state, once more, another time," going back to Old English
ongeagn, ongeæn, ongēan, ongān, ongegn, ongēn, agēn (Northumbrian
ongægn, ongǣn), (compare parallel compounds in Old Saxon
angegin "once more, toward," Old High German
ingagan, ingegin "in opposition") from
on-, a- 1on,
1a- +
-geagn (going back to Germanic
*gagna-, whence Old High German
gagan "towards, against," Old Norse
gagn- "against, counter, through") or
-gegn (going back to Germanic
*gagni-, whence Old Saxon & Old High German
gegin "against," Old Frisian
jēn, Old Norse
gegn)
Note:
It has been assumed that certain Old English forms, such as ongeagn, reflected an original *gagna-, and others, such as ongegn, an original *gegni-, though the evidence for the latter in Old English is not entirely clear. The rare instances of ongegn could represent "palatal monophthongization" of ongeagn, while ongēn would be a contraction of ongegn—this would leave only reflexes of *gagna- in Old English. Old English ongān (continued in Middle English ayan) apparently represents a monophthongization of ongēan after the crest of the diphthong had shifted forward. Middle English ayen, the most common southern form well into the 14th century, may be the outcome of either ongēan or ongēn. The form ayein would appear to directly continue ongegn. Originally northern again is presumed to have the velar /g/ from Old Norse i gegn. The shortened vowel in the usual pronunciation of again is probably due to against, where it was conditioned by the final consonant cluster. The origin of Germanic *gagna-, *gegni- (Gothic correspondent lacking) is obscure.
