what are some of its similar gestures ?
In the United Kingdom, Ireland, Australia and New Zealand, the V sign, "two-fingered salute" or "the fingers", when given with back of the hand towards the recipient, serves a similar purpose.
The finger
In the United Kingdom, Ireland, Australia and New Zealand, the V sign, "two-fingered salute" or "the fingers", when given with back of the hand towards the recipient, serves a similar purpose. 
what did the middle finger mean in ancient greece It is an obscene hand gesture. and in modern era ? In the film "Speedy" (1928), Harold Lloyd's character gives himself the finger into a distorting mirror at Luna Park, about 25 minutes into the film.
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The finger [SEP] Similar gestures
In the United Kingdom, Ireland, Australia and New Zealand, the V sign, "two-fingered salute" or "the fingers", when given with back of the hand towards the recipient, serves a similar purpose. According to a Royal Shakespeare Company synopsis of the play "Henry V", a "two-fingered salute" appeared in the Macclesfield Psalter of (in the Fitzwilliam Museum, Cambridge), "being made by a glove in the psalter's marginalia". George H. W. Bush, former President of the United States, accidentally made the gesture while on a diplomatic trip to Australia. In countries where Spanish, Portuguese or French are spoken, and especially in Spain, Portugal, Brazil and France, the gesture involving raising a fist and slapping the biceps on the same arm as the fist used, sometimes called the "bras d'honneur" (French), "corte de mangas" (Spanish), "manguito" (Portugal), "dar uma banana" (Brazil), or Iberian slap, is equivalent to the finger.