The term gentleman (from Latin gentilis,belonging to a race or "gens",and "man",cognate with the French word gentilhomme and the Italian gentil uomo or gentiluomo),in its original and strict signification,denoted a man of good family,analogous to the Latin generosus (its invariable translation in English-Latin documents).In this sense the word equates with the French gentilhomme (nobleman),which latter term was in Great Britain long confined to the peerage.The term "gentry" (from the Old French genterise for gentelise) has much of the social class significance of the French noblesse or of the German Adel,but without the strict technical requirements of those traditions (such as quarters of nobility).This was what the rebels under John Ball in the 14th century meant when they repeated:
When Adam delved and Eve span,
Who was then the Gentleman?[1]
John Selden in Titles of Honour,(1614),discussing the title "gentleman",speaks of "our English use of it" as "convertible with nobilis" (an ambiguous word,like 'noble' meaning elevated either by rank or by personal qualities) and describes in connection with it the forms of ennobling in various European countries.
To a degree,"gentleman" signified a man who did not need to work,and the term was particularly used of those who could not claim nobility or even the rank of esquire.Widening further,it became a politeness for all men,as in the phrase "Ladies and Gentlemen,..." and this was then used (often with the abbreviation Gents) to indicate where men could find a lavatory,without the need to indicate precisely what was being described.
In modern speech,the term is usually democratised so as to include any man of good,courteous conduct,or even to all men (as in indications of gender-separated facilities).