addera (present tense adderer, past tense adderte, past participle <span class="searchmatch">addert</span>, passive infinitive adderast, present participle adderande, imperative adder)...
present tense adderer, passive adderes, simple past adderte, past participle <span class="searchmatch">addert</span>, present participle adderende) (arithmetic) to add, add up addisjon dividere...