fain (adj.) 1
obliged, forced, compelled
2H4 II.i.140 [Hostess to Falstaff] I must be fain to pawn both my plate and the tapestry of my dining-chambers
2H6 IV.ii.154 [Cade to Dick, of the sale of Maine] thereby is England mained and fain to go with a staff
AW IV.iii.235 [First Soldier to Parolles] by the General's looks, we shall be fain to hang you
AYL IV.i.54 [Rosalind as Ganymede to Orlando] horns; which such as you are fain to be beholding to your wives for
E3 III.i.182 [Mariner to King John, of the navies] we perforce were fain to give them way
H8 V.iv.56 [Man to Porter, of a gang of boys] delivered such a shower of pebbles that I was fain to draw mine honour in, and let 'em win the work
MM IV.iii.151 [Lucio to Isabella] I am fain to dine and sup with water and bran
MM IV.iii.169 [Lucio to disguised Duke, of making a woman pregnant] I was fain to forswear it
MW II.ii.24 [Falstaff to Pistol] I myself sometimes ... am fain to shuffle
TG I.i.120 [Speed to Proteus] I perceive I must be fain to bear with you [also: sense 2]