Open English Wordnet
Nouns
(n)reluctance, hesitancy, hesitation, disinclination, indispositiona certain degree of unwillingness“a reluctance to commit himself”, “his hesitancy revealed his basic indisposition”, “after some hesitation he agreed”
(n)hesitation, waver, falter, falteringthe act of pausing uncertainly“there was a hesitation in his speech”