1The bottom or lower side or surface of something: the butterfly’s wings have a mottled brown pattern on the underside
More example sentences
- There is also a rear loading ramp which forms the underside of the rear fuselage.
- Seeds appear to have been produced on the underside of the leaf, with the leaf edges rolled over to form an enclosing chamber.
- He can see crows nesting on the underside of tree branches, and leaves fluttering down to the sky.
Definition of underside in:
- The British & World English dictionary