薄油層

oil sheet

oil / fat / grease / petroleum / to apply tung oil, paint or varnish / oily / greasy / glib / cunning

surname Bo

thin / cold in manner / indifferent / weak / light / infertile

meager / slight / weak / ungenerous or unkind / frivolous / to despise / to belittle / to look down on / to approach or near

see 薄荷[bo4 he5]

to pile on top of one another / layer; stratum / floor (of a building); story / (math.) sheaf / classifier for layers