Costa Rican Spanish
The unique or distinguishing characteristics of Costa Rican phonetics include the following:
- Many Costa Rican speakers pronounce the letter "r" not as an alveolar trill, as is done in most Spanish-speaking regions, but as an approximant consonant as is done in English-speaking countries.
Second person singular pronouns 
Usted is the dominant second person singular pronoun in Costa Rican Spanish. Some speakers use only "usted" in addressing others, never "vos" or "tu." Others use both: usted y vos, according to the situation.
"Vos" is a second person singular pronoun used by many speakers in certain "familiar" relationships or informal contexts. Voseo is most commonly used in the university context between students. It is also widely use between friends, family, people of the same age etc. Some adults use "vos" in order to address children or juveniles, but other adults address everyone regardless of age or status with "usted." Costa Ricans tend to use 'usted' with foreign people.
"Tú" is not used in Costa Rican Spanish, However, due in part to the influence of Mexican television programming, Costa Ricans are familiar with tuteo, and some television viewers, especially children, have begun to use it in limited contexts.
Costa Rican Spanish has a number of expressions unique to Costa Rica.
- mae: "dude".
- pura vida literally means "pure life" but can also be the response to the question "how are you?" or to say "thank you"; it was used for the scientific name of the crab Kiwa puravida.
- tico/tico: "Costa Rican".
- pajilla: "drinking straw".
Tiquismos (colloquial expressions) and pachuquismos are used quite frequently in Costa Rica. The latter is a form of popular street Spanish and can be very vulgar and offensive if used in the wrong context. You won’t be able to find the definition of many of these words in a standard Spanish dictionary. If you do locate any of them, they probably will not have the same meaning as in Costa Rica. Learning colloquial expressions can be a guide to understanding the humor and character of the Costa Rican culture.  
Here is a couple of examples of Costa Rican slang.
- Mae, ese chante es muy tuanis: "Dude that house is pretty cool".
- Esta panta no me cuadra porque me chima las piernas: "I don’t like these shorts because they chafe my legs".
See also 
- Jergas de habla hispana Spanish dictionary specializing in slang and colloquial expressions, featuring all Spanish-speaking countries, including Costa Rica.