The verb ocher ('to notch') can take the prefix en-, and this single YBB attestation can be interpreted as a spelling variant of this compound, cf. enocher. However, English and Anglo-Norman show evidence of a lexicalized contraction of the 'n' of the indefinite article (resulting in the noun noche¹), and this attestation suggest the existence of of a verbal derivative of that noun, *nocher (currently not attested) with a prefix a-.