► 形容動詞多大  [ただい]  [liter]    
meaning:  big  rank: 3☆ 
彼は
ジャズ界に多大な
影響を
与えた ⇨ He had a major influence on the jazz world  
(☛ Usually positive)多大  [ただい]  [liter]    
meaning:  many  rank: 3☆ 多大な
御支援頂き誠に
有難うございます ⇨ I’d like to thank for a lot of the support that I have received
More examples:- 彼は物理学で多大な業績を挙げた ⇨ He has accomplished a lot in physics
 - 彼は物理学の発展に多大な功績をあげた ⇨ He accomplished and contributed a lot to the development of physics