plural of try-hard

plural of Vickers hardness

plural of blow-hard

plural of water hardness

plural of total hardness

plural of die-hard

(idiomatic, informal) To cause difficulty or make trouble for someone. / (idiomatic, informal) To tease, kid or rib someone.

(idiomatic) In a difficult and inescapable position. / (idiomatic) Having the choice between two unpleasant or distasteful options; in a predicament or quandary.

(idiomatic) Established habits are difficult to change.

To acquire knowledge through failure or any other undesirable experience.