zoological gardenEnglishMerriam-Webster Dictionaryroblematical'>problematical), recondite, serious, spiny, stubborn, thorny, ticklish, trickybruising, burdensome, exhausting, labored, onerous, oppressive, stressfulroblematical'>problematical), recondite, serious, spiny, stubborn, thorny, ticklish, trickybruising, burdensome, exhausting, labored, onerous, oppressive, stressfulzoological garden — MW · Shobdo