Slang / Jargon (1) Acronym. GLTA · Good Luck To All. So now you know - GLTA means "Good Luck to All" - don't thank us. Looking for the definition of GLTA? Find out what is the full meaning of GLTA on Abbreviations. The meaning of GLTA is: Good Luck to All. What does GLTA mean? This page is all about the meaning, abbreviation and acronym of GLTA explaining the definition or meaning and giving useful information.