use·less 
/ˈju:sləs/ adjective
/ˈju:sləs/ adjective [more useless; most useless] : not at all useful : not doing or able to do what is needed
▪ a dull, useless knife ▪ The tent is useless in wet conditions. : not producing or able to produce the effect you want ▪ I made a useless attempt at fixing the leak. ▪ It's useless trying to change her mind. = It's useless to try to change her mind. ▪ Drugs are useless in treating the condition.
▪ a dull, useless knife ▪ The tent is useless in wet conditions. : not producing or able to produce the effect you want ▪ I made a useless attempt at fixing the leak. ▪ It's useless trying to change her mind. = It's useless to try to change her mind. ▪ Drugs are useless in treating the condition.
— use·less·ly adverb
▪ The ship's sails flapped uselessly.
▪ The ship's sails flapped uselessly.
— use·less·ness noun [noncount]
