Word: lightspeed
Part of speech: Noun
Syllables: light
speed
Definition: The speed of light (in vacuum unless another medium is specified)
Morphemes:
Affix: light
Language: en
PoS: Adjective
Meaning: Having light; bright; clear; not dark or obscure.
Affix: speed
Language: en
PoS: Noun
Meaning: The state of moving quickly or the capacity for rapid motion.