[1] i.e. (in each case) the general concept or process of this.
[2] Aorist middle participle, masculine nominative singular; evidently quoted from somewhere. See further, next note.
[3] This addition differentiates the third person singular, aorist indicative active, of the verb ὀνίημι -- perhaps quoted from Homer, Odyssey 14.67 -- from the similar-looking but unrelated aorist middle participle (masculine singular nominative) of the verb ὠνέομαί and the noun cognate with it, with which the entry has begun. LSJ entries for the two verbs at web addresses 1 and 2.