Receptive learning refers to words whose meaning you understand when you hear them. All adults have an understanding of the words they hear, or explained differently, the meaning of the word, even though they might not be speaking them or using them themselves. You might think that statement odd, however, think about a foreign language for a minute. You might understand a spoken word in French, but of which is difficult to pronounce, and of which you otherwise leave unsaid. If you understand the word, but aren’t saying it or expressing it, then you have receptive language.
I grew up speaking French in school. In most cases, I would be considered fluent, however, my receptive language far surpasses my expressive language. Since French is a language I use only very rarely, many words that I would otherwise understand if heard, are difficult for me to recall as I speak. Therefore, my expressive French is left wanting, making it difficult for me to carry on a conversation without struggling. At a certain stage a baby has the same ability, they react to a sign or word because they understand what it means, but can’t yet use it. Once a baby reaches about 14-16 months, they will respond to simple verbal commands like “Go get your ball” or “Where is Dad?” This doesn’t mean that a baby is capable of saying these sentences however.
The same holds true for signing, and often a baby will understand the meaning of a word before they are successfully able to sign them. Signing is referred to as expressive language because it means that a baby can express the words themselves. Stated a bit differently, expressive language involves using words to express thoughts. A baby that has receptive language, however, is one that is nearing the milestone where they are able to use expressive (sign) language. Some of these clues are listed more inclusively above but generally an understanding of receptive language in a baby involves nonverbal clues such as 1) an obvious reaction to the sign 2) eyes seem to light up 3) baby wiggles in glee 4) arms flap 5) make excited sounds in response.
For example, if you ask a baby if they want MILK signed or said, and baby gets excited, you know that your baby understands what you are saying. This however, is wholly different that a baby who is able to make the sign for MILK and identify it in the room, or ask for it when thirsty, which is expressive. The point is that receptive language is a good indication that your baby is nearly able to make his first sign so keep an eye out for any of these clues as an indication of sign readiness.