The word 千岛湖 is formed by combining three characters: 千 (qiān), meaning "thousand", 岛 (dǎo), meaning "island", and 湖 (hú), meaning "lake". These characters are concatenated in sequence to create a compound term that literally describes a "thousand-island lake", referring specifically to a lake containing numerous islands. The formation directly uses the numeral 千 to quantify 岛, which then modifies 湖, resulting in a name that denotes a geographical feature based on its distinctive characteristic.