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Although this phrase can be found in the scientific literature, the intended readers are people who actually know what that means. There is a popular misconception that "ignited" refers to large-scale nuclear fusion, which happens about 30 million years later when the sun enter the Main Sequence, or when the sun becomes intensely bright, which happens long before it begins spewing anything out.
What we're dealing with here is the transition from protostar to star, which occurs when its net mass stops increasing.