The meaning of SECURELY is in a secure manner. How to use securely in a sentence. Everything is securely attached because anything that falls could cause a traffic accident below, and sudden weather can change everything. Find 54 different ways to say SECURELY, along with antonyms, related words, and example sentences at Thesaurus.com. Find 940 synonyms for Securely to improve your writing and expand your vocabulary. Definition of securely adverb in Oxford Advanced Learner's Dictionary. Meaning, pronunciation, picture, example sentences, grammar, usage notes, synonyms and more. Factsheet What does the adverb securely mean? There are four meanings listed in OED's entry for the adverb securely. See ‘Meaning & use’ for definitions, usage, and quotation evidence.