Syllable division derived from spelling — this word is not in the pronouncing dictionary, so no phonetic transcription is shown rather than a guessed one.
rightfield is a noun meaning "the piece of ground in the outfield on the catcher's right". It carries 2 recorded senses.
the piece of ground in the outfield on the catcher's right
the fielding position of the player on a baseball team who is expected to field balls in the right third of the outfield (looking from home plate)
Forms marked · are formed by the regular rule rather than recorded in the source data. English keeps a few hundred irregulars and the rest follow the pattern, so the rule is right far more often than not — but it is a rule, and the mark says so.
Definitions, synonyms and semantic relations for rightfield come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.