conjectural (adj.)

"depending on conjecture, implying a guess," 1550s, from Latin coniecturalis "belonging to conjecture," from coniectura "a conclusion, interpretation, guess, inference," literally "a casting together (of facts, etc.)," from past-participle stem of conicere "to throw together," from assimilated form of com "with, together" (see con-) + iacere "to throw" (from PIE root *ye- "to throw, impel"). Related: Conjecturally (mid-15c.); conjecturative (early 15c.).