to launder: to wash cloth or clothing clean by treading and scrubbing it.
TranslatabilityApproximateCertaintySettled
This is the household word for cleaning fabric, not the body. In the ancient world you washed clothes by soaking them, working in a cleansing agent, and then stamping or pounding them underfoot in water, which is why the same root names both the act and the worker who did it for a living. A different word covers bathing skin; this one stays with garments and cloth.
The word does its heaviest work in the laws of Israel's worship. Again and again a person who has touched something unclean must wash their clothes before they can rejoin the community, so the act is less about removing dirt than about being made fit to come near God. That ritual weight is what lets the prophets and poets pick the word up and apply it to the inner life.
When the word turns figurative, it keeps the picture of hard scrubbing. Asking God to wash you from sin borrows the image of a launderer working a stain out of cloth, and the prophets warn that some stains no amount of scrubbing will lift. The same root also names the launderer himself, and a well-known landmark, the launderer's field outside Jerusalem, takes its name from where this trade was done.
Nuances
1ato wash garments or cloth, especially to become ceremonially clean enough to approach God.
Names the concrete LABOR of washing by treading and beating, the work of a launderer cleaning cloth, so it normally takes garments as its object.Lev 13:54Lev 15:17
Carries a vivid figurative force for scrubbing away guilt as one scrubs a stain from cloth, picturing sin as a deep mark that ordinary washing cannot lift.Jer 2:22Jer 4:14
Tied to a place, the launderer's field, marking it as a known trade rather than a state of being.Isa 7:32Ki 18:17
Both
Both belong to the same purification ritual and are paired step by step: the defiled person launders the clothes and so becomes clean.Lev 14:8
Both are invoked together for inner cleansing from sin, the launderer's scrubbing standing alongside the plea to be made pure.Psa 51:2Psa 51:7
Names the resulting STATE of being clean or pure, not a physical act: a person, a house, or an object becomes ritually acceptable, often by a priest's formal verdict that it is clean.Lev 13:6Lev 13:13
Reaches into MORAL and inner cleansing, asking God to purify the heart from sin, not just the body from defilement.Psa 51:2Lev 16:30
Used of cleansing accomplished by water on the body or by ritual sprinkling, where the outcome is purity itself rather than the scrubbing of clothes.2Ki 5:10Num 19:12
Names the physical labor of getting cloth clean, done by treading and pounding the fabric, and it also names the tradesman who does it: the road outside Jerusalem where kings and prophets meet is identified as the washer's field.2Ki 18:17Isa 7:3Isa 36:2
It is the standing command of the purity laws: anyone who touches something unclean must wash their clothes before they can rejoin the camp, and that requirement is repeated dozens of times.Lev 11:25Lev 15:5Num 19:7
Because it is scrubbing rather than a result, it can be pictured as failing: a person may scour with the strongest soap and the guilt is still there.Jer 2:22Mal 3:2
Both
Both belong to the laundry picture of forgiveness, and one line of a psalm uses them together: the plea to be washed and the promised outcome of being whiter than snow.Psa 51:7
The prophets use each one for guilt treated as a stain on cloth, one asking whether the scrubbing will hold and the other promising that scarlet sins will come out white as snow.Jer 4:14Isa 1:18
Points at a color rather than an action: it says a thing has turned white, and that can happen with no washing involved at all, as when locusts strip a fig tree and leave its branches bare and pale.Jol 1:7
Carries a wholly separate sense of brickmaking, built on the word for a mud brick, where nothing is being cleaned or whitened: it is the slave labor of Babel and of Egypt.Gen 11:3Exo 5:7Exo 5:14
Describes people themselves being made white over time, refined through hard testing until what is left is pure.Dan 11:35Dan 12:10
Means to wash or scrub something clean by working it through water, the ordinary word for laundering clothes. The thing washed survives the process and comes out clean.Exo 19:10Lev 13:6
Is the standard term for ritual cleansing in the purity laws: a person who has touched something unclean washes the garments to be made fit to rejoin the community.Lev 15:5Num 19:19
Both
Both are pleas to God to remove sin in Psalm 51: the one asks to be scrubbed clean of guilt, the other asks for the record of wrongdoing to be wiped away. Together they show two pictures of the same forgiveness.Psa 51:2Psa 51:1
Means to wipe a surface so that what was on it is gone, the word for erasing writing, blotting a name out of a record, or wiping a dish.Num 5:23Pro 30:20
Often means to destroy completely, to obliterate people or a memory so that they no longer exist at all, with no thought of anything cleansed or preserved.Gen 7:23Exo 17:14
kavas in the other biblical languages
πλύνωGreek“to wash”the Greek verb for washing clothes, used in Revelation of robes made white, which carries this word's sense of laundering fabric clean.
This is the set word of Israel's purity laws: again and again a person who has touched something unclean must wash their clothes before they are counted clean.Lev 11:25Lev 15:5Num 19:19
It carries a moral picture too: the heart's guilt scrubbed clean like a stained garment, with the scouring so deep that no human washing could ever finish the job.Psa 51:2Jer 2:22
Because it is the trade of the launderer who beats and treads cloth, it also tags places and people by that craft, such as the field of the launderer outside Jerusalem.Isa 7:32Ki 18:17
Both
Both name the washing of cloth and clothing rather than the washing of the body, the launderer's work of scrubbing a garment clean.Exo 19:10Rev 7:14
Both stretch from the literal cleaning of cloth to a figure for a person being made clean before God.Psa 51:7Rev 22:14
In the New Testament this washing is almost always a picture, not a chore: robes made clean and white by the blood of the Lamb, standing for a life made right with God.Rev 7:14Rev 22:14
It can also name the plain everyday job of cleaning gear, as when fishermen wash out their nets after a night's work.Luk 5:2
What scholars say about kavas
The standard lexica treat kabas as the dedicated verb for laundering or fulling cloth, distinct from rachats (H7364) for bathing the body, with the worker (the fuller) named by the participle. HALOT and BDB note its concentration in the priestly purity laws, where washing garments is a rite of restored cleanness, and its figurative extension to the cleansing of sin in the Psalms and prophets. TDOT and TWOT trace the same act-and-agent pattern and the launderer's field toponym. There is no live debate over the verb's core sense.
Sources
HALOT, s.v. כבסlexicon
BDB, s.v. כבסlexicon
G. Andre, "כבס," in Theological Dictionary of the Old Testament (TDOT) 7:54-58dictionary