from
The Collaborative International Dictionary of English v.0.48
Scarf \Scarf\, n.
(a) In a piece which is to be united to another by a scarf
joint, the part of the end or edge that is tapered
off, rabbeted, or notched so as to be thinner than the
rest of the piece.
(b) A scarf joint.
[1913 Webster]
{Scarf joint}
(a) A joint made by overlapping and bolting or locking
together the ends of two pieces of timber that are
halved, notched, or cut away so that they will fit
each other and form a lengthened beam of the same size
at the junction as elsewhere.
(b) A joint formed by welding, riveting, or brazing
together the overlapping scarfed ends, or edges, of
metal rods, sheets, etc.
{Scarf weld}. See under {Weld}.
[1913 Webster]