Tulip Bulbs: A modified bud consisting of a thickened globular underground stem serving as a reproductive structure. Electric lamp consisting of a transparent or translucent glass housing containing a wire filament (usually tungsten). A rounded part of a cylindrical instrument (usually at one end). Anything with a round shape resembling a teardrop. Lower or hindmost part of the brain; continuous with spinal cord; (`bulb' is an old term for medulla oblongata). A rounded dilation or expansion in a canal or vessel or organ.