Charanthia means sandalwood. The context in which you have raised the inquiry is a shabad by Guru Nanak in Raag Gujri on Page 489 of Sri Guru Granth Sahib.
A bit of a historical background (to the best of my ability). It is common practise in India for the pundit to rub sandalwood on a piece of stone (ursa), and add a bit of water. This combination would give out a very fragrant smell and bits of this would be applied on the idol of God that was being worshipped.
Guru Nanak is explaining the concept of Naam Japna through the imagery of this exercise by stating in the following shabad:
Raag Goojaree, First Mehl, Chau-Padas, First House:(Page 489)
Tera Naam Kaaree Charanathia, Jee Man Ursa hoove
I would make Your Name the sandalwood, and my mind the stone to rub it on;