Unusual and challenging words

Pairs

optimist - glass half full, happy view, expecting a good outcome
Pessimist - gloomy, gloom and doom

lend
borrow

imply
infer

Emigrant - like exit, to leave
immigrant - like the word in, to move into a country
migrant - one who moves

Esoteric words
exotic - from the East, exciting and unusual
antithesis - opposite
epitome
cryptology - study of code
enigma - puzzle
esoteric
espionage - spying
fugitive person running away, usual from police
aesthetic - studying what is beautiful or pleasing to the eye, harmonious and stylish
ethics /morals
elegiac
misogyny
Psychology
psychiatry
sitcom
romcom
rookie - novice, new on the job
sociology
forensic medicine
patriarch rule by the 'fathers' i.e. men
matriarchy - rule by 'mothers' women
oligarchy - rule by the rich
geriatric old
haematology
ubiquitous - found everywhere
astrology using stars to predict the future or actions of types of character born each month
astronomy - scientific study of stars, the sky and universe, using telescopes and charts
Theology

Italian
cognoscenti