English

immask

From im- + mask.

Formed from in- + mask

Proto-Indo-European *h₁én ‘in’

Proto-Germanic *in ‘into’

English in-

Proto-Indo-European *mosgʷ- ‘netting, mesh, knot, loop’

…

Proto-West Germanic *maskā ‘mesh, net’

Medieval Latin masca

Italian maschera ‘mask, disguise’

Middle French masque ‘a covering to hide or protect the face’

English mask

Today it means

verb To cover, as with a mask; to disguise or conceal.

Language periods are conventional ranges, not dates for this word.