3 triangle or trigon
4 rectangle or quadrilateral or tetragon
5 pentagon
6 hexagon
7 heptagon
8 octagon
9 nonagon or enneagon
10 decagon
11 hendecagon
12 dodecagon
13 triskaidecagon or tridecagon
14 tetrakaidecagon or tetradecagon
15 pendedecagon
16 hexakaidecagon or hexadecagon
17 heptdecagon
18 octdecagon
19 enneadecagon
20 icosagon
