The term 'kind of arch' can refer to four different types of arches: OGEE (4 letters), matri (5 letters), skeen (5 letters), and LANCET (6 letters). An OGEE arch is an arch with a double curve, resembling an S-shape. A matri arch is a pointed arch with a pointed apex. A skeen arch is an arch with a concave curve on the top and a convex curve on the bottom. Finally, a LANCET arch is a tall, narrow arch with a pointed top.