Eustathius adapts there the received etymology for δεῖπνον, δεῖ + πόνος "one has to work", which is valid for the meaning "first meal of the day". Since for him δεῖπνον means "dinner" and refers to the last meal of the day, the etymology has to be adapted, which he does by changing the second element of the compound and relating it to ὕπνος "sleep". Plutarch had already tried a similar adaptation in order to account for the semantic difference between "first meal of the day" and "last meal of the day" (see δεῖπνον / διαναπαύω + πόνον). Here Eustathius gives explicitly both etymologies for δεῖπνον, one according to each meaning. It is not presented as a complementary etymology but it may have been in Eustathius' source (lost). Notice that he also gives here an etymology ex antonymo for ἄριστον "breakfast" (ἄρεος ἱσταμένου "when fighting begins"), which is designed for the military context of the Iliad and intended in opposition to the older etymology provided for δόρπον (δόρυ παύω "to cease fighting")