| Main Entry: | |
| Part of Speech: | noun |
| Definition: | train line |
| Synonyms: | elevated railway, line, metro, monorail, rail line, railway, streetcar line, subway, tracks, trolley line, tube, underground railway |
| Main Entry: | subway |
| Part of Speech: | noun |
| Definition: | underground railroad |
| Synonyms: | chute, metro, tube, underground |