Pro word meaning and definition

[noun] an argument in favor of a proposal
[noun] an athlete who plays for pay
[adv] on the affirmative side
[adjective] in favor of (an action or proposal etc.); "a pro vote"

\Pro-\ [L. pro, or Gr. ?. See {Pro}.] A prefix signifying before, in front, forth, for, in behalf of, in place of, according to; as, propose, to place before; proceed, to go before or forward; project, to throw forward; prologue, part spoken before (the main piece); propel, prognathous; provide, to look out for; pronoun, a word instead of a noun; proconsul, a person acting in place of a consul; proportion, arrangement according to parts.
\Pro\, prep. [L.; akin to prae before, Gr. ?, and E. for. See {For}, prep., and cf. {Prior}, a.] A Latin preposition signifying for, before, forth. {Pro confesso} [L.] (Law), taken as confessed. The action of a court of equity on that portion of the pleading in a particular case which the pleading on the other side does not deny. {Pro rata}. [L. See {Prorate}.] In proportion; proportion. {Pro re nata} [L.] (Law), for the existing occasion; as matters are.
\Pro\, adv. For, on, or in behalf of, the affirmative side; -- in contrast with {con}. {Pro and con}, for and against, on the affirmative and on the negative side; as, they debated the question pro and con; -- formerly used also as a verb. {Pros and cons}, the arguments or reasons on either side.

Morse code: .--. .-. ---