knob Copy link Outline 1. bulla (lit. a bubble2. umbĭlīcus (of the projecting k.s at the ends of scrolls)3. perh. pĭla (applicable to anything ball-shaped)4. nōdus (a knot or knob in wood)5. tŭber, ĕris (a knobby excrescence) • knob: 1. bulla (lit. a bubble: applied to various round objects): Vitr. 9, 8 (9), 12 (the head of a pin in a water-clock): cf. Cic. Verr. 4, 56, 124, aureae bullae [valvarum], knobs or studs. 2. umbĭlīcus (of the projecting k.s at the ends of scrolls): Mart. 2, 6, 11. 3. perh. pĭla (applicable to anything ball-shaped): v. ball. 4. nōdus (a knot or knob in wood): cf. Virg. Aen. 7, 507, stipes gravidus nodis, a knotty, knobbed club. 5. tŭber, ĕris (a knobby excrescence): Plin. 16, 16, 27. Also tuberculum, a lump or knob: used by Cels. of the round ball-end of a joint, 8, 1, med.