To ordain someone as a deacon or to invest someone with the office of deacon.
From 'deacon' with the verb-forming suffix '-ize' (like organize, standardize). This suffix transforms nouns into verbs meaning 'to make' or 'to cause to be' something.
The suffix '-ize' is one of English's most productive word-building tools, used to create verbs from nearly any noun, which is why you can 'deaconize' someone even if it's not a word you'll hear every day.
Complete word intelligence in one call. Free tier — 50 lookups/day.