Word: underside
Part of speech: Noun
Syllables: un
der
side
Definition: The side that is below or underneath, the bottom.
Morphemes:
Affix: under-
Language: en
PoS: Prefix
Meaning: Under (in any sense): insufficient, insufficiently, below what is correct; subordinate to; beneath or behind.
Affix: side
Language: en
PoS: Noun
Meaning: One half (left or right, top or bottom, front or back, etc.) of something or someone.