Usage: 8 forms in 14 verses
Form Translated As     In Verse(s)
κούφόν light LXX.1Sam.18.23
κούφοσ nimble LXX.Jer.46.6
was light LXX.2Sam.2.18
κούφον light LXX.2Kgs.20.10
κούφοισ light LXX.Eccl.9.11LXX.Isa.30.16
κούφοι Nimble LXX.2Sam.1.23LXX.Isa.30.16LXX.Lam.4.19
light LXX.1Chr.12.8
of light LXX.Isa.18.2
κούφησ a nimble LXX.Isa.19.1
κούφη it a light LXX.2Kgs.3.18
κουφότεροι Lighter than LXX.Jer.4.13

Liddell-Scott-Jones

κοῦφος (kouphos) light (in weight) G:A--C

κοῦφος, η, ον,

light, nimble, [Refs 8th c.BC+] adverb, κοῦφα ποσὶ προβιβάς stepping lightly on, [LXX+8th c.BC+] too buoyant, [Refs 5th c.BC+]

__2 metaphorically, easy, light, τελεῖν.. κούφαν κτίσιν to make achievement easy,[Refs 4th c.BC+]; κ. νύξ an easier night, of a sick person, [Refs 4th c.AD+]; περίπατος [Refs 1st c.BC+]; of government, light, κουφοτέραν βασιλείαν less oppressive, [Refs 5th c.BC+]; of an antagonist, easy-going, κουφότατος ἦν κρατήσας [Refs 4th c.BC+]
__3 unsubstantial, airy, vain, τὸ νέον.. κούφας ἀφροσύνας φέρον [Refs 5th c.BC+]; κ. πρᾶγμα a trifle, [Refs]; κ. γράμματα a small letter, [Refs 5th c.BC+]; of persons, ={κουφόνους}, [Refs 2nd c.AD+]; τὸ κοῦφον τοῦ νοῦ levity, [Refs 2nd c.AD+]
__4 light in point of weight, opposed to βαρύς, [Refs 5th c.BC+], etc.; κούφα σοι χθὼν ἐπάνωθε πέσοι may earth lie lightly on thee, [Refs 5th c.BC+]; κ. πνεύματα light airs, [Refs 5th c.BC+]
__4.b in Medicine texts in various uses, σικύαι κοῦφαι dry cuppings, [Refs 2nd c.AD+]; also κούφου μένοντος τοῦ ἰοῦ on the surface, [Refs 3rd c.AD+]; μὴν κ. the eighth month of pregnancy, [Refs 2nd c.AD+]; of food, easy to digest, light, [Refs 4th c.BC+]
__4.c of troops, light-armed, οἱ κ. τῶν στρατιωτῶν [Refs 5th c.BC+]
__4.d of ships, lightly-laden, [Refs 5th c.BC+]
__5 light, slight, ἁμαρτήματα [Refs 5th c.BC+]; κουφότερα γυμνάσια, opposed to ἀναγκαῖα, [Refs 4th c.BC+]
__6 empty, κεράμια [Refs 4th c.BC+] substantive, κοῦφον (i.e. κεράμιον), τό, jar, in plural, [Refs 3rd c.AD+]
__7 active, relieving, assisting, χερὶ κούφᾳ [Refs 5th c.BC+]: probably to be taken in this sense in [Refs 3rd c.BC+]
__II adverb -φως lightly, nimbly, κ. ὀροῦσαι [Refs 4th c.BC+]; κ. ἐσκευασμένοι, of soldiers, [Refs 5th c.BC+]; κ. ἔχειν to be relieved, [Refs 4th c.BC+]
__II.2 metaphorically, lightly, with light heart, κουφότερον μετεφώνεε [Refs 8th c.BC+]; κ. φέρειν, opposed to δεινῶς φ., [Refs 5th c.BC+]; διάγουσα κούφως doing well, of a patient, [Refs 5th c.BC+]
__II.3 lightly, with ease, [Refs 4th c.BC+]

LSJ Scripture Refs: LXX.Eccl.9.11