-ˈsüz ə n noun
Usage: usually capitalized S
Etymology: black-eyed (from black (I) + eyed ) + Susan (the name)
1. : either of two coneflowers, one ( Rudbeckia hirta ) of central and eastern No. America and one ( R. serotina ) of the southeastern U.S., having flower heads with deep yellow to orange rays and dark conical disks
2. : flower-of-an-hour
3. also black-eyed susan vine : a tropical African vinelike herb ( Thunbergia alata ) with yellow flowers having a dark purple center