underside
n. countable B2 Upper Intermediate US //ˈəndɝˌsaɪd// UK //ˌʌndəsˈaɪd// un·der·side
n. the side or part of something that faces the ground or is hidden underneath. You often look here to find things that are tucked away or out of sight.
n. the bottom or lower surface of an object, typically the part that is hidden from view or directed toward the ground.
The mechanic checked the underside of the car for rust.
If you flip over the leaf, you might find tiny insect eggs attached to the underside.
The documentary explores the dark underside of the fashion industry, revealing the systemic exploitation that occurs behind the glamour of the runway.
From under- + side.
Usage
Often used with the preposition 'of'. Can be used figuratively to describe the hidden, unpleasant aspects of a situation.