Definition of 立会い (たちあい)
たちあ
                        立会い
たちあい
tachiai
Common word
noun
1.
presence (e.g. of an observer), observation, observer, witness(sometimes written 立ち合い)
2.
trading session (at an exchange)
Other readings:
                立会【たちあい】
、立ち会い【たちあい】
                Related Kanji
| 立 | stand up, rise, set up, erect | 
| 会 | meeting, meet, party, association, interview, join |