What does thoroughly mean?
Thoroughly is an adverb meaning “completely,” “in every respect,” or “with great care and attention.” It can describe the full scope of an action, as in “The team reviewed the proposal thoroughly,” or the care taken to perform it, as in “The instruments were cleaned thoroughly.” The word is flexible enough for everyday conversation and formal professional writing, including legal, academic, medical, and technical contexts. Its force often comes from suggesting that no important detail has been overlooked. “Thoroughly” can therefore imply either that something has been done in full or that it has been done meticulously. It is more emphatic than simply saying that an action was done, and more precise than vague expressions such as “very well.” Related to the adjective thorough and the noun thoroughness, it is especially useful when completeness, careful inspection, or sustained attention is important.
adverbIn a complete or exhaustive manner, with full attention to every part or aspect.
- With complete or exhaustive attention; in every detail.
- In a way that leaves nothing undone; completely.
"The investigators searched the abandoned building thoroughly before declaring the search complete."
"The investigators searched the abandoned building thoroughly before declaring the search complete."
"Before publishing the results, she checked every source thoroughly."
Thoroughly carries its promise in its roots: it means doing something all the way through.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does thoroughly come from?
Thoroughly was formed in the early 16th century from the adjective thorough and the adverbial suffix -ly. Thorough developed in Middle English from a word connected with Old English þurh, meaning “through” or “from side to side,” and acquired its sense of being complete or exhaustive during the medieval period. English words such as through and throughout preserve the same ancient Germanic root.
Related word forms
How thoroughly is actually used
Thoroughly is neutral in register and common in formal, professional, and everyday contexts. Depending on context, it may emphasize either the completeness of an action or the care with which it is carried out.
Easily confused with thoroughly
Thorough is an adjective describing something complete or done carefully, whereas thoroughly is the adverb describing how an action is performed.