One word Substitution 

• One who loves mankind- Philanthropist 
• One who hates mankind- Misanthropist
• One who loves language- Philologist 
• One who hates language- Misologist
• One who loves marriage- Philogamist
• One who hates marriage - Misogamist
• One who distrusts and dislikes everybody- Misocapnic
• One who beliefs easily- Credulous
• One who is violently hostile to establish beliefs, customs, traditions, institutions - Iconoclast
• One who is easily fooled- Gullible
• One who is able to talk very quickly- Volluble
• One who collects postage stamps- Philatelish
• One who collected coins- Numismatist
• One who flirts with women- Philanderer
• a man known for seducing women and having many lovers- Casanova
• One who flirts with men - Paramour
• One who does not marry especially for the religious obligation- Celibate
• One who retires from society to live a solitary life- Recluse
• One who is citizen of the world- Cosmopolitan 
• One who eats human flesh- Cannibal
• One who eats flesh- Carnivorous 
• One who abstains from alcoholic drinks and restrict others to take so- Tee-totaller
• One who is indifferent to pain and pleasure- Stoic
• All type of excitement- Stolid
• One who believes in God- Theist
• One who does not belive in God- Atheist 
• One who believes that God exists every object of nature- Pantheist
• One who does not believe in God of anything except material things- Agnistic 
• One who displays one's knowledge- Pedant
• A person having the same name as another- Namesake
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