Syllable division derived from spelling — this word is not in the pronouncing dictionary, so no phonetic transcription is shown rather than a guessed one.
second-string is an adjective meaning "being a replacement or substitute for a regular member of a team". It carries one recorded sense.
being a replacement or substitute for a regular member of a team
“a second-string pitcher”
Definitions, synonyms and semantic relations for second-string come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.