Hi Derek, 1. echar, lanzar, arrojar; (they could both mean "to throw") You can add "tirar" to the list, it also has a similar meaning. They're all synonyms, and if there is NO context, they're largely interchangeable. If there is context, then it depends... - "tirar" has a subcontext of "discard", e.g. tirar algo a la basura, - "lanzar" is more related to throwing something with some precision, or to certain distance, like a projectile, e.g. lanzar una pelota - echar usually has a subcontext of "out of somewhere", e.g. echar a alguien de casa (kick someone out from home), and also throw something over someone/something: echar un cubo de agua fría, echar un abrigo sobre la cama - arrojar is like echar, but with more momentum/force, e.g. los piratas arrojaban a sus victimas por la borda del barco; el policía se arrojó contra el asaltante But, in many cases, they´re all mostly interchangeable. For example, to "toss a coin" you can lanzar una moneda, tirar una moneda, or echar una moneda. Arrojar una moneda wouldn´t be right (unless you were throwing it hard, with the intention of hurting someone) 2. desperdicio, desecho; These are tricky, similar but different. They´re both "remains" from something else, which are likely to end up in the trash. However: - Desecho is something unusable, useless and unwanted. - Desperdicio is something that should be desirable, but has to be discarded for some reason. For example: you order food in a restaurant, but you don´t eat it all - what´s left on the plate is a desperdicio, not a desecho. 3. descomponerse, corromperse. These have very many meanings, especially figurative. I´ll stick to the literal meanings. Descomponerse: if it refers to organic material, it means "to rot" (most frequent). But if it refers to a complex structure, it can mean to dissolve. Corromperse: it´s a bit like "rot", but "descomponerse" is usually a consequence of time/decay, and corromperse is the corrossive effect of an external substance (corrode)

Not to be more confusing but there is also the word echar with can mean "to throw"