Requisite, a.
Etymology: [L. requisitus, p. p. requirere; pref. re- re- + quaerere to ask. See Require.]
Required by the nature of things, or by circumstances; All truth requisite for men to know. Milton.
Syn. -- Necessary; needful; indispensable; essential. -- Req"ui*site*ly, adv. -- Req"ui*site*ness, n.
1 other Webster entry under this spelling
Requisite (rkw-zt), n.
That which is required, or is necessary; something indispensable. God, on his part, has declared the requisites on ours; what we must do to obtain blessings, is the great business of us all to know. Wake.
Shades of meaning
Fernald has no entry of its own for requisite; he lists it under necessary, necessity.
Where he writes about it:
That which is requisite (or required) is so in the judgment of the person requiring it, but may not be so absolutely; thus, the requisite is more a matter of personal feeling than the indispensable. — from necessary