[1] The phrase is adjectival, composed of two adjectives, καλός ("beautiful") and ἀγαθός ("good" or "virtuous"), the second of which is combined by crasis with καί "and" to form κἀγαθός.
Werner Jaeger summarizes it as "the chivalrous ideal of the complete human personality, harmonious in mind and body, foursquare in battle and speech, song and action".
Translations such as "gentleman" or "knight" have traditionally been suggested to convey the social aspect of the phrase, while "war hero" or the more cynical "martyr" are more recent versions, and emphasise the military element.
Its recorded usage dates from the second half of the 5th and in the 4th century B.C.. For example, in Plato's Lysis, a young man is described as imbued with kalokagathia.
This second adjective means "good" in a broad and general sense, and had no particular physical or aesthetic connotations, but could describe a person's excellence of character (ethical virtue), for example their bravery.