Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
fors-an, adv. [ellipt. for fors sit an; v. fors, II. A. and forsitan, and cf. fortan and fortassean], perhaps, perchance, peradventure (poet. and in post-Aug. prose): me miseram, forsan hic mihi parvam habeat fidem, Ter. Eun. 1, 2, 117; Lucr. 6, 729: forsan et haec olim meminisse juvabit, Verg. A. 1, 203; forsan miseros meliora sequentur, id. ib. 12, 153: huic uni forsan potui succumbere culpae, id. ib. 4, 19: et mihi forsan tibi quod negarit, Porriget hora, Hor. C. 2, 16, 31: pernicies Tibi paratur, forsan et miserae mihi, Phaedr. 2, 4, 7: transierant binae forsan trinaeve Calendae, Mart. 10, 75, 7: quem decreto sermonem praetenderit, forsan aliquem verum auctores antiqui tradiderint, Liv. 3, 47, 5; 10, 39, 14: occurrat mihi forsan aliquis, Quint. 1, 5, 6; 12, 1, 31; Col. 3, 9, 1: et tu forsan audire nolis, Curt. 3, 2 (dub. v. Zumpt ad Curt. 3, 5, 11).
In law Lat., as for example, for instance, Dig. 48, 5, 34, § 1.