AVERRUNCATOR, a form of long shears used in arboriculture for "averruncating" or pruning off the higher branches of trees, etc. The word "averruncate" (from Lat. averruncare, to ward off, remove mischief) glided into meaning to "weed the ground," "prune vines," etc., by a supposed derivation from the Lat. ab, off, and eruncare, to weed out, and it was spelt "aberuncate" to suit this; but the New English Dictionary regards such a derivation as impossible.
Note - this article incorporates content from Encyclopaedia Britannica, Eleventh Edition, (1910-1911)