let alone is a verb and adverb meaning "leave unchanged or undisturbed or refrain from taking". It carries 2 recorded senses.
leave unchanged or undisturbed or refrain from taking
“leave it as is”
“leave the young fawn alone”
“leave the flowers that you see in the park behind”
Definitions, synonyms and semantic relations for let alone come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.