Synonyms of assiduous

assiduous

adjective

ə-ˈsij-wəs 

as in diligent

involved in often constant activity

the fascinating sight of assiduous ants carrying food into the anthill

Synonyms & Similar Words

• diligent
• engaged
• busy
• employed
• active
• occupied
• industrious
• working
• preoccupied
• sedulous
• laborious
• immersed
• bustling
• hopping
• concentrating
• absorbed
• tied-up
• focused
• buzzing
• lively
• indefatigable
• tireless
• humming
• engrossed
• operational
• operating
• vigorous
• vibrant
• operative
• functioning
• animated
• going
• untiring
• hardworking
• energetic
• intent
• flourishing
• thriving
• knee-deep
• astir
• functional
• swamped
• happening
• running
• living
• alive

Antonyms & Near Antonyms

• idle
• unemployed
• inactive
• free
• unoccupied
• latent
• passive
• quiescent
• sleepy
• slow
• unbusy
• dormant
• inert
• lifeless
• asleep
• dull
• dead
• inoperative
• nonoperating

Synonym Chooser

How is the word assiduous different from other adjectives like it?

Some common synonyms of assiduous are busy, diligent, industrious, and sedulous. While all these words mean "actively engaged or occupied," assiduous stresses careful and unremitting application.

assiduous practice

When is it sensible to use busy instead of assiduous?

Although the words busy and assiduous have much in common, busy chiefly stresses activity as opposed to idleness or leisure.

too busy to spend time with the children

When could diligent be used to replace assiduous?

The words diligent and assiduous are synonyms, but do differ in nuance. Specifically, diligent suggests earnest application to some specific object or pursuit.

very diligent in her pursuit of a degree

When would industrious be a good substitute for assiduous?

While in some cases nearly identical to assiduous, industrious implies characteristic or habitual devotion to work.

industrious employees

When can sedulous be used instead of assiduous?

The meanings of sedulous and assiduous largely overlap; however, sedulous implies painstaking and persevering application.

a sedulous investigation of the murder

Example Sentences

Recent Examples of assiduous

The timely message is told in a frequently absurd yet affecting style, including through the assiduous mo-cap of its A-list cast (which includes Léa Seydoux, Elle Fanning, and George Miller). —Lewis Gordon, Vulture, 3 Dec. 2025

The body, which was created in 1829, has been assiduous in ensuring its members receive fair payment for their work in the digital age. —Melanie Goodfellow, Deadline, 14 Nov. 2025

Amid this totalizing assault, the nutria’s assiduous gnawing may seem a relatively mild insult; in the state’s coastal-threat index, the nutria would come in sixth place. —Nathaniel Rich, Harpers Magazine, 20 Aug. 2025

Record sales were up, and due to his assiduous efforts, Colonel never tired of reminding Snow, all sorts of new, high-paying opportunities in radio and television were starting to open up. —Jem Aswad, Variety, 5 Aug. 2025