Word: 老大 (lǎodà) 老大 dictionary entry lǎodà old age; very; eldest child in a family; leader of a group; boss; captain of a boat; leader of a criminal gang Full dictionary entry for 老大 Example sentences using 老大 2 sentences, showing page 1 of 1. 老大比老二大三岁。 Lǎodà bǐ lǎo'èr dà sān suì. The eldest is three years older than the second child. 这群孩子里，他是老大。 Zhè qún háizi lǐ, tā shì lǎodà. Among this group of kids, he is the leader.