from The American Heritage® Dictionary of the English Language, 5th Edition.

  • adjective Showing or characterized by persistent attention or untiring application: synonym: diligent.

from The Century Dictionary.

  • Constant in application; attentive; devoted: as, a person assiduous in his occupation; an assiduous physician or nurse.
  • Constant; unremitting: applied to actions.
  • Synonyms Sedulous, diligent, active, busy, constant, patient, persevering, laborious, unceasing, indefatigable, untiring. See assiduity.

from the GNU version of the Collaborative International Dictionary of English.

  • adjective Constant in application or attention; devoted; attentive; unremitting.
  • adjective Performed with constant diligence or attention; unremitting; persistent.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

  • adjective Hard-working, diligent or regular (in attendance or work); industrious.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • adjective marked by care and persistent effort


from The American Heritage® Dictionary of the English Language, 4th Edition

[From Latin assiduus, from assidēre, to attend to : ad-, ad- + sedēre, to sit; see sed- in Indo-European roots.]

from Wiktionary, Creative Commons Attribution/Share-Alike License

From Latin assiduus, from assidere ("to sit down to"), from ad- ("to") + sedere ("to sit").


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  • Citation on fungus garden.

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