Abarim Publications' online Biblical Hebrew Dictionary
דכך דכא דכה דוך
The four forms דכך (dkk), דכא (dk'), דכה (dkh), and דוך (dwk) are obviously related in form and their meanings all have to do with being crushed, broken or contrite. These forms literally denote the compromising of consistency, that is, a turning into dust of something that was previously solid. Their object is sometimes bones (Psalm 38:8) but mostly people's minds or lives (Psalm 143:3, Job 4:19). These forms are accompanied by the going consolation that YHWH is near to the crushed and oppressed (Isaiah 57:15, Psalm 34:18).
דכך
The root דכך (dkk) isn't used as verb in the Bible and only two sparsely used derivatives remain:
- The adjective דך (dak), meaning crushed or oppressed. It's used three times to generally describe the oppressed (Psalm 9:9, 10:18, 74:21) and once the victims of a lying tongue (Proverbs 26:28).
- The feminine noun דכה (dakka), which is used only once, to describe someone wounded (presumably castrated) by means of crushing (Deuteronomy 23:2).
דכא
The verb דכא (daka') is almost exclusively used to describe the effects of oppression, whether wrongful or just. Hence the poor and needy are crushed in court (Proverbs 22:22), Israel's leaders crush their people (Isaiah 3:15) and the wicked crush the righteous (Psalm 94:5). God in turn crushes oppressors (Psalm 72:4) and the wicked (Job 34:25) and even his servant (Isaiah 53:5). On a purely theological stage, YHWH crushes Rahab (Psalm 89:10).
This verb's derivatives are:
- The adjective דכא (dakka'), meaning contrite or crushed (Psalm 34:18 and Isaiah 57:15 only).
- The identical noun דכא (dakka'), meaning dust. This noun occurs only in Psalm 90:3, which reads "You turn man back into dust and say: 'Return, O children of men'," which might as well be interpreted as "You convert people by making them contrite".
דכה
The root דכה (dkh) is a by-form of דכא (daka') and is used in the same way. It occurs about six times and only in the Psalms (Psalm 10:18, 44:19, 51:17). Its sole derivation is the masculine noun דכי (doki), meaning a crushing. It's used only in Psalm 93:3, where it denotes the crushing waves of the ocean.
דוך
The verb דוך (duk) and its derived feminine noun מדכה (medoka) occur both once and in the same sentence. In Numbers 11:8 we read how the Israelites would gather Manna, grind it in mills or crushed (דוך) it into mash (מדכה), boiled it and made it into cakes.