straight off is an adverb meaning "without delay or hesitation; with no time intervening". It carries one recorded sense.
without delay or hesitation; with no time intervening
“he answered immediately”
“found an answer straightaway”
“an official accused of dishonesty should be suspended forthwith”
“Come here now!”
Definitions, synonyms and semantic relations for straight off come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.