Denshi Jisho — Online Japanese dictionary

碌 ろく good; satisfactory; worthy; decent
Na-adjective, Usually written using kana alone 
碌な ろくな satisfactory; decent
Common word, Ateji (phonetic) reading, Pre-noun adjectival, Usually written using kana alone 
碌に ろくに well; enough; sufficient
Common word, Adverb, Usually written using kana alone 
陸な ろくな satisfactory; decent
Pre-noun adjectival, Usually written using kana alone 
碌々 ろくろく hardly; barely; inadequately (with negative grammatical constructions)
Adverb 
碌碌 ろくろく hardly; barely; inadequately (with negative grammatical constructions)
Adverb 
碌すっぽ ろくすっぽ (before neg. verb) (not) enough; (in)sufficiently; (un)satisfactorily
Adverb, Usually written using kana alone 
碌ずっぽ ろくずっぽ (before neg. verb) (not) enough; (in)sufficiently; (un)satisfactorily
Ateji (phonetic) reading, Adverb, Usually written using kana alone 
碌でなし ろくでなし bum; good-for-nothing; ne'er-do-well
Noun, Usually written using kana alone 
碌すっぽう ろくすっぽう (before neg. verb) (not) enough; (in)sufficiently; (un)satisfactorily
Ateji (phonetic) reading, Adverb, Usually written using kana alone 
碌でもない ろくでもない good-for-nothing; worthless
Expression, Adjective, Usually written using kana alone 

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