the quality of being firm, faithful, unchanging

fixedness

a seriousness in wanting to do something successfully

perseverance

loyalty, faithfulness; accuracy; exactness

faithfulness in a relationship

a fibre or bundle of fibres carrying messages concerning feeling and movement between the brain and all parts of the body; condition of being easily excited, worried, irritated

daring, boldness

the constant effort to achieve something

diligence, hard work

a formal expression of opinion by an official meeting; something one makes up one's mind to do; the ending (of a doubt, problem etc) by supplying an answer

determination, strong will

a serious decision; to decide (something), especially with determination

decision, determination

diligence, stubbornness

diligence, stubbornness

the ability, willingness, to allow and accept opinions, beliefs, customs, physical types, behaviour etc different from one's own

fortitude, grit