pipe + clay
pipeclay (countable and uncountable, plural pipeclays)
pipeclay (third-person singular simple present pipeclays, present participle pipeclaying, simple past and past participle pipeclayed)
- To whiten by application of pipeclay.
- 1938, Xavier Herbert, Capricornia, Chapter VII, p. 92, 
- The walls were lined with paper-bark, pipe-clayed and panelled with polished bloodwood.
- (slang, dated, Britain) To clear off.
- to pipeclay accounts