One Heart in Chinese / Japanese...

一心 literally reads as “one heart” in Chinese, Japanese Kanji, and old Korean Hanja.

Colloquially or figuratively, it means: wholeheartedly; heart and soul; of one mind; wholeheartedness; one's whole heart; with the whole mind or heart; one mind in heart.
I'm not kidding, all of those came right from the dictionary for this one title. In Buddhism, this can refer to the bhūtatathatā, or the whole of things; the universe as one mind, or a spiritual unity.

In Japanese, this can be the female given name, Hitomi.

齊心協力 is a Chinese proverb that means “to work with a common purpose,” “to make concerted efforts,” “to pull together,” or “to work as one (or as if with one heart).”

專心 makes a word that means “paying attention with your heart.”

It's often translated as “dedication,” as in “be absorbed in” or “concentrate one's efforts.” It's also used to mean “with the single mind,” “whole-heartedly,” “paying attention,” “undivided attention,” “concentration (-ed),” “engrossed,” “devotionally (listening/watching),” and/or “attentive.”

The first character means “for a particular person, occasion, or purpose,” “focused on one single thing,” “concentrated,” and sometimes, “special.”

The second character means “heart” or “mind” by itself.

My favorite translation, which comes from the Oxford Advanced Chinese/English Dictionary, is, “wholehearted devotion.”

If it seems like the meaning of this word is quite open, you are correct. The context in which the word is used matters a lot. It can mean different things depending on how you use it. This makes it kind of nice as you can decide what this means to you (within some limits). This is always positive in meaning, so even if a Chinese person reads it differently than you, it will still have a good meaning.

In Japanese, they tend to use a variation of the second character which has one less stroke. If you want your calligraphy written this Japanese form, please click on the Kanji shown to the right instead of the button above. Note: Japanese and Chinese people will recognize either form.

See Also:  Faith | Devotion

獻身 is used to describe being so devoted to something that you will make sacrifices for that goal/thing/person.

You can also translate this word as any of the following:

This can be a dedication to or for someone but is often used as a dedication or making sacrifices for your country, public service, or a cause. For instance, an Olympic athlete makes great sacrifices to train in his/her sport for their country and compatriots.

While the form shown to the upper-left is considered an ancient Japanese version, in modern Japan, they use the simplified version of the first Kanji (shown to the right). Click on the Kanji at the right instead of the button above if you want this modern Japanese version.

If you are looking for a more religious meaning of devotion, see Faith.

See Also:  Confidence | Dedication