Healing up

Our narrator, Hermann Karlovich, is nothing if not self-conscious. He boarded a metaphorical bus when embarking on his narrative:

Vladimir Nabokov, Despair (1966).

I was surprised to see “heal up” here. I think of it as contemporary (right now) American language, but the Oxford English Dictionary has a citation from 1676: “A fontanel had been made in the same leg, which he was forced to heal up.”

Related reading
All OCA Nabokov posts (Pinboard)

[First published as Отчаяние [Otchayanie] in a Russian literary journal in 1934; then in book form in 1936; then in Nabokov’s English translation in 1937; then in revised form in 1966.]