1. thought
ふと、ある思いが頭に浮かんだ。Suddenly, a thought crossed my mind.
2. imagination; mind; heart
3. desire; wish; hope; expectation
理解したいっていう思いも強い。I also have a strong desire to understand.
4. love; affection
e.g. Ａ思いのＢ for 'B who loves A'
貴方は弟思いの良いお兄さんです。You are a good older brother who cares about your younger brother.
5. feelings; emotion; sentiment; experience
だから、母の思いは痛いほど分かった。That is why I understood my mother's feelings painfully well.