ECISD may refer to:

• Ector County Independent School District, a public school district based in Odessa, Texas
• El Campo Independent School District, a public school district based in El Campo, Texas
• Edinburg Consolidated Independent School District, a public school district based in Edinburg, Texas

• Spiny sow-thistle
• Spiny sow thistle
• Spiny sowthistle
• Spiny spider crab
• Spiny Spider Crab
• Spiny sturgeon
• Spiny-tailed goanna
• Spiny-tailed lizard
• Spiny-tailed monitor
• Spiny tailed monitor
• Spinytail Iguana
• Spinytail lizard
• Spinytail Lizard
• Spiny Tenrec
• Spiny Terrapin
• Spiny terrapin
• Spiny tree frog
• Spiny Tree Porcupine
• Spiny waterflea
• Spiny water flea
• Spin-½
• Spin–charge separation
• Spin–lattice relaxation
• Spin–spin relaxation
• Spione