Taru adjective, Adverb taking the 'to' particle
dense (e.g. fog, dust, etc.); thick
Usually written using kana alone
車は砂ぼこりをもうもうとあげて走っていた。The car raised a cloud of dust. vague (as in being unable to think clearly); dim
Usually written using kana alone
Also written 濛濛【もうもう】、朦朦【もうもう】、朦々【もうもう】