What does clog mean?
Clog functions as both a noun and a verb in English. As a verb, it means to block or obstruct a passage — a pipe, drain, artery, or road — so that whatever should flow through it cannot do so freely; this is by far the most common use today, appearing constantly in phrases like 'clogged drains' and 'clogged arteries'. As a noun, it has two main senses: a heavy shoe with a thick sole, traditionally made of wood and associated with workers in the Netherlands and northern England, and the actual blockage itself. Figuratively, a clog can be anything that hinders or weighs down progress, as in 'a clog on economic growth'. The word carries mildly negative connotations when used of obstructions, suggesting something unwanted and inconvenient. Its everyday usefulness lies in describing both physical blockages and, more abstractly, impediments to movement or advancement.
To block or fill up a passage, channel, or opening so that movement or flow through it is hindered or prevented.
"Grease from the kitchen had clogged the pipes."
Often used with 'up': 'clog up the works'.
A heavy shoe with a thick sole, typically made of wood; also, a blockage that obstructs a passage.
"The dancers wore wooden clogs that clicked on the stone floor."
Standard plural, used chiefly for the footwear sense; the blockage sense usually appears as an uncountable or singular reference.
"She bought a new pair of leather clogs for the summer."
The word 'clog' once meant a lump of clod or earth before it ever meant a shoe — and Dutch sailors' wooden klompen may be its most famous cousins.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of clog
Clog entered English in the Middle English period, originally meaning a lump or mass of earth or wood — essentially a clod. It likely derives from a Germanic root related to 'clot' and 'clod'. By the sixteenth century it had come to mean a wooden-soled shoe, presumably from the wooden material of which such shoes were made, and the senses of 'blockage' and 'to block' developed naturally from the idea of something solid lodged in a passage. Cognates include Dutch 'klok' (a wooden shoe) and related Germanic forms.
Related word forms
How clog is actually used
The verb sense (to block) is the most frequent in modern usage, especially in medical contexts ('clogged arteries') and household contexts ('clogged drains'). The noun referring to footwear is common in British English and in references to traditional Dutch or Lancashire dress. The figurative noun sense ('a clog on progress') is somewhat formal and now less common.
Easily confused with clog
A clock is a timekeeping device, while a clog is either a wooden-soled shoe or something that blocks a passage — the words differ by only one letter but share no meaning.