Complex sentence: According to Diogenes Laërtius, the philosopher was named "Aristocles" (Ἀριστοκλῆς) after his grandfather, but his wrestling coach, Ariston of Argos, dubbed him "Platon", meaning "broad," on account of his robust figure.
Split into simpler sentences: According to Diogenes Laërtius, the philosopher was named "Aristocles" (Ἀριστοκλῆς) after his grandfather. Diogenes' sources account for this fact by claiming that his wrestling coach, Ariston of Argos, dubbed him "Platon", meaning "broad," on account of his robust figure.