single-mindedly; intently; devotedly
Describes doing something with unwavering focus, putting all one's energy into it, often to the exclusion of other things. Can be used adverbially or as a na-adjective.
彼はひたすらに小説を書き続けた。
He kept writing his novel single-mindedly.
His devoted efforts bore fruit.
He kept studying single-mindedly, without a break.
I earnestly hoped for my family's safety.
She kept apologizing over and over.
一生懸命 highlights effort and hard work put into a task, whereas ひたすら focuses on undivided, repetitive concentration on one thing.
ひたすら is the natural modern word for doing something single-mindedly, corresponding to the rare, old-fashioned 'earnestly' sense of 一向に.
ひたすら stresses single-minded devotion to one activity, while ただただ stresses that a feeling or state is nothing but one thing, often with strong emotional color.
ひたすら is the natural modern word for doing something single-mindedly, while the same meaning of 一向 is an older, less-used literary sense.
Very rare single-kanji form; archaic or highly literary.