Some word pairs that seem like cognates are not. A small proportion of look-alikes are false cognates, so called because they don’t share the same meaning. These false friends can get you in trouble. In French the noun luxure appears to be a cognate for the English word luxury, but luxure means “lust.” It would be a faux pas—that’s the French phrase for “false step, or social blunder”—to say luxure when you are complimenting your supervisor’s cologne. In German if you were to identify a man with a shaved head by calling him bald, you’d get a blank stare because bald means “soon.” In Spanish if you feel ashamed, it’d be best not to say you feel embarazada, which means “pregnant.”
Some English–Spanish cognates are not identical because of the connotations, or shades of meaning, in one language. For instance, an inferior is a subordinate in both the English and Spanish workplace, but it is derogatory only in English. The cognates suburbs and suburbios both indicate areas outside the city limits, but the Spanish word usually connotes slums. And you would not describe your digestive problems by using the word constipado, because it means “congestion” of the nasal variety.