λύπας λύπη λύπην λύπης
Apparently a primary word; sadness -- grief, grievous, + grudgingly, heaviness, sorrow.
λύπας (lupas) − 1 Occurrence
λύπη (lupē) − 7 Occurrences
λύπην (lupēn) − 5 Occurrences
λύπης (lupēs) − 3 Occurrences