A
aerobescque, asymmetry
B
banner, biomorphic, and bifid, that is, divided into two by a deep split
C
circle or curvilinear
D
diamond
E
echinuliform, resembling small spines; effigurate, having an outline with a definite form. If I add more objects it can be called ennead, that is, any group of nine objects.
F
frame
G
garland
H
halved
I
illionic, illusionistic
J
jointed. Another term not used here is janiform, i.e., having two faces
K
keyhole (sorry, a stretch, I know)
L
laurel or linear
M
mirrored
N
nebulous and negative space
O
oval; olivary, which is olive-shaped; ooidal or egg-shaped
P
panelled, portioned, and phallic
Q
quadrant
R
radial or radiating
S
serpentine, symmetrical, sequenced; sigmate and sigmoid, which both mean shaped like an S
T
triangular, trans vexed
U
unified, undulating
V
vulviform, vivisection, vraisemblance and verisimilitude, versal, and finally, villiform, which is, having the form or shape of velvet.
W
wreathed
X
xiphoid or sword-shaped
Y
yin yang, and ypsiliform, from the Finnish for Y
Z
zig zag, zosteriform-shaped like a belt or girdle, zygomorphous, i.e., bilaterally symmetrical, and zepplinistic.
Of course, the zebra finch would make a very small zepplin.