Conundrum [noun]

● Riddle

● Mystery

● Enigma

● Puzzlement

● Poser

● Mystification

● Problem

● Why

● Brain-teaser

● Closed book

● Conundrum

● Riddle

● Enigma

● Brain-teaser

● Dilemma

● Quandary

● Problem

● Question

● Predicament

● Mystery

● Puzzle

● Headache

● Clue

● Questioner

● Secret

● Ate

● Trade-off

● Paradox

● Dichotomy

● Imbroglio

● Sticky wicket

● Trilemma

● Brainteaser

● Contradiction

● Cognitive dissonance

● Ambiguity

● Pitfall

● Logjam

● Uncertainty

● Oddity

● Impasse

● Stalemate

● Challenges

● Paradoxes

● Issue

● Poser

● Bugbear

● Mess

● Complexities

● Nightmare

● Woes

● Difficulties

● Equation

● Incongruity

● Crunch

● Bottleneck

● Shortcoming

● Carriwitchet

● Hot potato

● Malady

● Wrangle

● Imponderables

● Mismatch

● Simultaneous equations

● Stumbling block

● Obstacle

● Bugaboo

● Phenomenon

● Incongruence

● Minefield

● Hurdle

● Constraint

● Situation

● Quagmire

● Oxymoron

● Complication

● Kerfuffle

● Duality

● Troubles

● Contretemps

● Perplexities

● Imbalance

● Shortage

● Malaise

● Implications

● Squabble

● Ironies

● Disjunction

● Crux

● Fallacy

● Dearth

● Snafu

● Scenario

● Disparity

● Brouhaha

● Crisis

● Nebulousness

● Morass

● Litmus test

● Perils

● Enigmatist

● Paradoxology

● Realities

● Affliction

● Paradigm

● Upshot

● Tradeoff

● Ramifications

● Pickle

● Muddle