List: word usually written using kana alone

popular  usually written using kana alone  noun  noun (generic) 

• sweet potato (Ipomoea batatas)

popular  usually written using kana alone  noun  noun (generic)  Internet slang 

• mackerel (esp. the chub mackerel, Scomber japonicus)
• server (esp. in an online game)

popular  usually written using kana alone  noun  noun (generic) 

• coral

popular  JLPT N2  expression  usually written using kana alone 

• first, firstly, first of all, to begin with, in the beginning, at the beginning
• Introduction, Preface

popular  rarely used kanji form  JLPT N3  usually written using kana alone  い adjective  adjective (generic) 

• skillful, skilful, skilled, good, expert, clever (expression, trick, etc.), apt, appropriate
• delicious, tasty, good, nice
• good (deal, idea, etc.), profitable, promising, lucky, fortunate, successful, satisfactory, splendid

popular  search-only kana form  JLPT N1  female term  usually written using kana alone  pronoun 

• I, me

popular  gikun or jukujikun  usually written using kana alone  noun  noun (generic) 

• bigleaf hydrangea (Hydrangea macrophylla), French hydrangea

popular  gikun or jukujikun  JLPT N2  usually written using kana alone  noun  noun (generic) 

• cousin (female)

popular  search-only kanji form  usually written using kana alone  adverb 

• besides, furthermore, on top of that
• and yet, nevertheless, even so

popular  rarely used kanji form  usually written using kana alone  noun  noun (generic) 

• ginger (Zingiber officinale)