Note: Latin perīculum has traditionally been explained as a derivative from a proposed Indo-European verbal base *per- "test, risk," seen also in perītus "practiced, experienced," experior, experīrī "to put to the test, attempt, have experience of, undergo" (see experience entry 1) and opperior, opperīrī "to wait, wait for"; these have been compared with Greek peîra "trial, attempt, experience," peiráomai, peirâsthai "to make a trial of, attempt," émpeiros "experienced" (see empiric)—going back to *per-i̯a—and more tentatively with Germanic *fērō "pursuit, danger" (see fear entry 2). This *per- "test, risk" is then taken further as a semantic derivative of *per- "cross, pass" (see fare entry 1). Alternatively, if the formative -i- represents the Indo-European present-tense suffix *-ei̯-/-i-, Latin peri-/perī- in these words fits naturally with Indo-European *perh₃-/pr̥h₃- "bring forth, give rise to, produce" (if taken as a middle verb "give rise to within oneself, experience, undergo"), with *pr̥h₃-i- yielding Latin pariō, parere "to give birth to" (see parturient entry 1) and *perh₃-ei̯- yielding the per-ī- of perīculum, etc. It is unclear if the base of experior and opperior contains par- or per-, as the simplex verb is not attested. (Cf. Michiel de Vaan, "PIE i-presents, s-presents, and their reflexes in Latin," Glotta, Band 87 [2011], pp. 23-36.)