To adorn with emblems; to decorate with emblematic designs (a rare or archaic term).
From emblem plus the rare suffix -ish (not the common -ish meaning 'somewhat,' but an older verb-forming suffix from Old English -iscan, similar to embellish).
Emblemish is practically archaic now, but it follows the same pattern as embellish and abolish—all from Old English -ish verb formations, showing language layers where newer -ize verbs have replaced these older -ish formations.
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