A Grammatical Dictionary of Botanical Latin

Timber, “growing trees or their wood; “Eng. law: trees (as oak, ash, elm over 20 years old) that are part of a freehold and may not be cut by a life tenant; a wooded area, forest; a standing tree or its trunk; wood used for or suitable for building or for carpentry; something that is made of wood, such as a wooden gate, fence, ost; a large squared or dressed piece of wood; lumber” (after WIII); see woodland.

Tigellum,-i (s.n.II), abl. sg. tigello (following Jackson): also Tige, pr. teej (Fr., tige), ‘stem;’ Tigel = Tigelle, Tigella, Tigellus, “a miniature or initial stem, used for a) caulicle or hypocotyl, b. plumule” (Jackson) [perhaps dim. > L. tignum,-i (s.n.II), a piece or stick of timber; a trunk of a tree, a log, beam (Lewis & Short), e.g. dim. tigillum,-i (s.n.II), a small piece of wood].

Tignum,-i (s.n.II), abl. sg. tigno: building material, syn. trabs, q.v.; a piece or stick of timber, the trunk of a tree, a log or beam, a plank; see bar, beam.

Trabs, gen.sg. trabis (s.f.III), abl. sg. trabe, nom. & acc. pl. trabes, gen. pl. trabium, dat. & abl. pl. trabibus: a cut or prepared piece of wood, a plank, a piece of lumber or timber; a single cross-bar on a trabeculate peristome tooth; syn. tignum,-i (s.n.II), q.v. [> L. trabs,-is (s.f.III), a tree trunk, a cut length of a trunk]; see beam, wood.

TIMBER: TheLaw.com Law Dictionary & Black's Law Dictionary 2nd Ed.:

Wood felled for building or other such like use. In a legal sense it generally means (in England) oak, ash, and elm, but in some parts of England, and generally in America, it is used in a wider sense, which is recognized by the law. The term “timber,” as used in commerce, refers generally only to large sticks of wood, squared or capable of being squared for building houses or vessels; and certain trees only having been formerly used for such purposes, namely, the oak, the ash, and the elm, they alone were recognized as timber trees.... (March 25, 2018).