Definition - What does Lateral Bud mean?
Each node on the shoot of a vine can develop into a lateral bud or a latent bud, the lateral bud is the main axillary bud and grows the first lateral shoot during the growing season. The lateral bud is known as the main bud, and the lateral shoot grows during the first season, if a shoot does not grow from the lateral bud, it will die.
WineFrog explains Lateral Bud
It is important that during the first growing season a shoot grows from the lateral bud. The production of a first shoot allows the grapevine to grow more shoots and canes out of the secondary and tertiary buds during the next growing seasons. The lateral bud is the first to bud to form on the leaf axil and gives way to the first shoot. Some vine growers feel it necessary to trim or remove the lateral shoot while others believe the lateral shoot acts as a training mechanism for future shoots. Whether the lateral buds will grow shoots depends on environmental and genetic factors during the growing season.