Given to the first-born of twins, regardless of the child's sex. In Yoruba belief, Taiwo is sent out first by the second twin, Kehinde, to see what the world is like. The literal meaning is close to "the first to taste the world."
Source: Yoruba twin-naming tradition, cross-referenced across Wikipedia (Taiwo, Kehinde), Duke University "Sacred Arts of the Black Atlantic" (Ère Ìbejì twin figurine collection), and Yoruba community naming-guide sites (ejireokin.com)