A Grammatical Dictionary of Botanical Latin

Bur, more typical spelling than 'burr,' “1. a prickly-headed fruit; applied to the chestnut [Castanea; Aesculus], Arctium, and the like; 2. the female inflorescence of the hop, when the stigmas forming the Brush are visible” (Jackson); "any rough or prickly, bristly envelope of a fruit whether a pericarp, a persistent calyx, or an involucre, as the husk of a chestnut, the hull of a mature cotton boll, the cone of a hop plant at the time of flowering" (WIII}: lappa,-ae (s.f.I), abl. sg. lappa; see also burl; see tribulus,-i (s.m.II).

Arctium Lappa L., Lappa is an old generic name.

Lappago,-inis (s.f.III), abl. sg. lappagine: “a plant resembling a bur” (Lewis & Short): Urena Lappago

Lappula,-ae (s.f.I): a little bur: Myosotis Lappula [Malvaceae]; Triumfetta Lappula

bur-like, lappaceous: lappaceus,-a,-um (adj.A), lappulaceus,-a,-um (adj.A); cf. bristly.

echinatus,-a,-um (adj.A): echinate, armed with numerous rigid hairs or straight prickles or spines.

muricatus,-a,-um (adj.A): muricate, i.e. rough with short hard points or tubercles like the shell of Murex.

tribuloides (adj.B): resembling the genus Tribulus, Caltrop; (usu. of fruit) with conspicuous spines, prickles or thorns