Synonyms of abysmal in English:

very bad, dreadful, awful, terrible, frightful, atrocious, disgraceful, deplorable, shameful, woeful, hopeless, lamentable, laughable, substandard, poor, inadequate, inferior, unsatisfactory

rotten, appalling, crummy, pathetic, pitiful, useless, lousy, shocking, dire, poxy, the pits

British duff, chronic, a load of pants, pants

North American vulgar slang chickenshit

profound, extreme, utter, complete, thorough, deep, endless, immeasurable, boundless, incalculable, unfathomable, bottomless