(a) The European elder (Sambucus nigra); hilder tre; (b) hilder tre, ?the European alder [see alder n. (1)]; (c) in place names [see Smith PNElem. 1.274].
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(a) Wise, prudent; knowledgeable; also, cunning, skilled, able [the precise gloss is determined by the context]; witter and wale (ware, wise), wise and witter; witter of eie, observant
(b) requiring……