Answer: Optometrists
Explanation: Ophthalmologists are the doctors who treats eye ailments, perform surgeries and administer drugs.
Oculist was an earlier term used for Ophthalmologists.
Then, there are (ophthalmic) opticians who perform the same function as optometrists while the (dispensing) opticians supply the lenses and glasses as per your optometrist's or ophthalmologist's suggestion.
Answer: Periodontist
Explanation: The specialists who treat your teeth have their own specialisation.
Exodontist deals with tooth extraction, Orthodontists straighten your teeth, Endodontists treat the inside pulp of your teeth & perform root canal therapy while Periodontists are the specialists who treat your gums.
Orthos mean to straighten or correct, Endon means inside while Peri refers to around.
Answer: Graphologist
Explanation: "Graphos" refers to writing and logos refers to science. So, someone who practices the science to study handwriting is Graphologist.
Answer: Obstetrician
Explanation: Gynecologist is a professionals who deals with the treatment of female reproductive organs. However, the one who actually delivers the babies is an Obstetrician.
Answer: Entomologists
Explanation: Entomology is the special branch of science which deals with the study of insects. Etymology which sounds similar deals with the study of origin of words and how their meanings have changed with time.
Answer: Dermatologist
Explanation: We should remember that, "derma" refers to skin. So, a word which has "derma" is likely to be related to skin. Logos refers to science.
Dermatitis is a skin condition which is treated by a Dermatologist. While taxidermist is some one who deal with the business of skin stuffing, mounting etc., pachydermist is not a meaningful word at all.
Answer: Psychiatrist
Explanation: The word "psyche" refers to mind. So, whenever you see "psyche" associated with any other word, it should immediately occur to you that this word has got something to do with mind.
Now, someone whose mind has lost contact with reality is called a Psychotic.
Psychiatrist is someone who practices the medical way to improve people's health through drugs, sessions and other things.
Psychologist has studied psychology and understand how people behave in particular situations. This professional finds a place even in the industry where workers are required to be kept happy and motivated.
Psychoanalyst on the other hand could be a physician, psychiatrist or psychologist who has received special training to delve into the unconscious mind using the techniques devised by Sigmund Freud. He reviews your experiences, traumas, feelings, thoughts to understand your present worries, fear, behaviour etc.
Answer: Geriatrician
Explanation: "Geras" is a greek word that refers to "old". So, someone who deals with the medical conditions of elderly is a Geriatrician.
However, there's another professional who deals with the social, economic, retirement related and sexual problems of elderly is called a Gerontologist.