The Chinese word for peninsula is
半岛

bàn dǎo

Chinese Definition

peninsula
1. 名词. 半岛
Components
半
1. half
全國人口的一半 - half of the national population
一磅半 - 1½ pounds
十點半 - 10:30
2. very little
3. halfway, partially, semi-
半醉半醒 - partially in a stupor, partially awake (attention, zh, please check)
4. (Hong Kong, informal, neologism) half past
九半 - half past nine
5. usage. 半 + noun means "and a half".
半塊麵包 - half a loaf of bread
兩塊半麵包 - two and a half loaves of bread
岛
1. Simplified form of 島