一向(いっこう)にcompletely, absolutely, totally, (not) at all, (not) a bit, (not) in the least, earnestly, intently, determinedly

一向(いっこう)に雨(あめ)がやまない。

The rain doesn't stop at all.

彼(かれ)は一向(いっこう)に帰(かえ)ってこない。

He hasn't come back at all.

一向(いっこう)に眠(ねむ)くならない。

I'm not getting sleepy at all.

担任(たんにん)：「彼(かれ)の態度(たいど)は一向(いっこう)に良(よ)くなりませんね。」教頭(きょうとう)：「はい。そろそろ三者(さんしゃ)面談(めんだん)をしますか。」

Homeroom teacher: "His attitude isn't improving at all." Vice principal: "Yes. Shall we have a three-way meeting soon?"

息子：「一向に熱が下がらないんだ。」母：「つらいね。もう一回、違う病院に行ってみる？」

Son: "My fever just won't go down." Mother: "That's tough. Do you want to try going to a different hospital again?"