second gear is a noun meaning "the gear that has the second lowest forward gear ratio in the gear box of a motor vehicle". It carries one recorded sense.
the gear that has the second lowest forward gear ratio in the gear box of a motor vehicle
“he had to shift down into second to make the hill”
Definitions, synonyms and semantic relations for second gear come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.