Green’s Dictionary of Slang

bona adj.

also bonna, bonar, boner
[Ital. buono, good]

(Ling. Fr./Polari) good, pleasant, agreeable.

[[UK]Mundus Muliebris Preface: The Presents which were made [...] were a Ring, a Necklace of Pearl, and perhaps another fair Jewel, the Bona paraphanalia of her prudent Mother].
[UK]Swell’s Night Guide 58: Stunning place – bona shicksters, and clys worth touching, eh, cully? [Ibid.] 68: I’ve tumbled on a donna, who has been doing the multa bonna fakement, pallarying the slavies down the haries and she has done stunning, and copped a lummy slum of bonna scran.
[UK]Kendal Mercury 3 Apr. 6/2: Mind ye, it must be bona prog vitch this hanimal vil polish his ivories hon.
[UK](con. 1840s–50s) H. Mayhew London Labour and London Poor III 47/2: If we has a good pitch we never tell one another, for business is business. If they know we’ve a ‘boner’ pitch, they’ll oppose, which makes it bad. [Ibid.] 208/1: ‘Is it bona?’ That is, – Is it good?
[UK]P.H. Emerson Signor Lippo 45: Well, you look bona, and so does your mate?
[UK]J. Ware Passing Eng. of the Victorian Era 10/2: Artful Fox (Music-hall, 1882). A nonsense rhyme for ‘ box’. You capture the first liker at him in a snug artful fox at some chantin ken where there’s a bona varder in serio comic, and Isle of Francer engaged. – From Biography of the Staff Bundle Courier, the gentleman who accompanies ‘seriocomics’ from music-hall to music-hall when ‘doing turns’.
[UK]K. Williams Diaries 24 Oct. 15: Went to the matelots’ bar — met 2 marines — very charming. Bonar shamshes.
[UK]R. Hauser Homosexual Society Appendix 3, 167: Bonar, good, nice, beautiful, etc.
[UK]Took & Feldman Round the Horne 22 May [BBC radio] I saw an advertisement which read – ‘Get away from it all – spend your holiday at the Bona Guest House, Bogmouth’, so I decided to throw a few things into a bag and give it a try.
[US]B. Rodgers Queens’ Vernacular 35: boner (Brit gay sl fr Parlyaree It bona = good) attractive, beautiful ‘He really has a bonar bod, small wonder he’s on the game.’.
[UK]Flame : a Life on the Game 117: A big butch number walked in. Dead bona.
[US]M. Coward in Verbatim 24:2 n.p.: The Jules and Sand sketches often begin with some variation on the salutation ‘How bona to vada your dolly old eek again,’ meaning ‘How good to see your nice old face again’.
[SA]K. Cage Gayle.
[NZ]W. Ings ‘Trolling the Beat to Working the Soob’ in Int’l Jrnl Lexicog. 23:1 64: Polari words like bona (good), naff (bad or distasteful), cove (friend or mate), lucody (body) [...] appeared in wider gay slang.
[UK]P. Baker Fabulosa 289/2: bona good [...] bona lavs best wishes! [...] bona nochy good night! [...] bona vardering attractive.
[UK]R. Milward Man-Eating Typewriter 27: She wanted me to stay [...] free from bona old-fashioned family values.

In compounds

bona omee (n.) (also bona homey, boner homey) [omee n. (2)]

(camp gay) a pleasant person, lit. a ‘good man’.

[UK]F. Norman in Encounter n.d. in Norman’s London (1969) 65: I haven’t got time to listen to you two talking about the bona homeys that you’d like to have.
[UK]F. Norman Guntz 99: The other queen remarked that he was a ‘boner homey’.
[US]J. McCourt ‘Vilja de Tanquay Exults’ in Queer Street 394: Into that flouncy cerise and bust her arse, / To keep the omi bonas on the rut.