Glossary of TEFL Acronyms

SLA - Second Language Acquisition: When SLA is used as a noun, it refers to the body of research into language acquisition by non-native speakers. It's generally not used like, "I studied the child's SLA"; rather, "L2 acquisition" would probably be used instead (L2 is the common abbreviation of "second language"). The field of SLA research investigates the influences on and rate of L2 development.

By the way, SLA is also a common acronym in other fields. It can mean Service Level Agreement (a contract between a service provider and a client), and it's the organizational acronym for the Special Libraries Association (see www.sla.org).