Daijirin (a comprehensive single-volume Japanese dictionary first published in 1988)

trot

derive the kana for a mora onsetted with /p/ from the kana for a mora onsetted with /h/

agreement, consent, assent

semi-voiced mark; mark that changes Japanese h/f into p: は (ha) > ぱ (pa)

great majority

great majority

(traditional Chinese phonology) a voiced onset obstruent / (traditional Japanese phonology) a mora with a voiced onset obstruent

The handakuten, which indicates that a kana with an initial of h- should be pronounced with p- (i.e. ha with a handakuten is pronounced as pa). It is also sometimes used with k- kana to indicate ng- (a phoneme that is usually an allophone of /g/).

problem child