Asentence-ending that denotes that you wonder whether or not something is the case.
is the more direct andmale variant of でしょう.
Just like normal だろう, this is a male variant. it can also be used with でしょう to make it more female.
行くだろう They will probably go.
彼は私を誘うだろうか。 I wonder whether or not he will ask me out. (masculine, so pretty gay)
彼女は本当に彼氏を欲しいのだろうか。 I wonder whether or not she really wants a boyfriend. (masculine).
with の
Can also be a form with the explanatory の・んだ (It then also follows the rules of the explanatory の・んだ, with leading な)
私たちのチームは勝てるのだろうか。 I wonder whether or not our our team can win. (masculine)