add oil

add fuel to the fire

To worsen a conflict between people; to inflame an already tense situation.

add insult to injury

To further a loss with mockery or indignity; to worsen an already unfavorable situation.

add up

To make sense; to be reasonable or consistent.

burn the midnight oil

To work studiously, especially late into the night.

oil and water

Two things which are incapable of mixing or coexisting harmoniously with each other.

oil burner

A device whose operation causes apparent combustion of lubricating oil.

oil trash

An uncultured, rowdy roughneck employed in the petroleum industry, especially a "white trash" person if used negatively.

pour oil on troubled waters

To calm, appease or quiet a person or situation.