حك

6 تَحَاكَّا تحاك تحاكا [ They scratched, scraped, rubbed, grated, chafed, or fretted, each other; or] their two bodies became in collision, and each of them scratched, &c., (حَكَّ,) the other. (K.) ― -b2- هٰذَا أَمْرٌ تَحَاكَّتْ فِيهِ الرُّكَبِ, and ↓ احتكّت, (tropical:) This is a case in which the knees are in contact, and in collision, is a saying by which is meant equality of station or rank, or the sitting together upon the knees in contending for superiority in glory or excellence or nobility. (TA.) ― -b3- [تحاكّ also signifies It became scraped off, or rubbed off, by degrees; the verb in this sense being similar to تساقط &c.: see حُكَاكَةٌ.]