directrix (dÉªËrÉktrÉªks; daÉª-) n. 1. (Mathematics) geometry a fixed reference line, situated on the convex side of a conic section, that is used when defining or calculating its eccentricity. 2. (Professions) a directress [C17: New Latin, feminine of director] diâ¢recâ¢trix (dÉªËrÉk trÉªks, daÉª-)
e-Visa [edit]. Turkish e-visa can be obtained prior to arrival or on arrival (for a higher cost). Citizens of these countries are eligible to apply for a multiple entry e-Visa which allows to stay up to 90 days (unless otherwise stated):1  Antigua and Barbuda. 2  Armenia #. - Countries whose citizens are allowed to enter Turkey with their expired passports (up to 5 years). 3 - Allowed to enter Turkey with their passports or ID cards expired within the last year. Turkish e-visa can be obtained prior to arrival or on arrival (for a higher cost).
American citizens traveling to Turkey on U.S. passports must obtain a visa. Currently, holders of all types of passports can purchase a 90-day sticker visa at the port of entry for $20 cash if they are traveling to Turkey as tourists.ffective February 1, 2012, the Turkish authorities will implement new regulations allowing a maximum stay of 90 days within a 180 day period. The new regulation will not make any changes to the visa requirements for travel to Turkey but it will affect how long U.S. Citizens can remain in Turkey.