The Spanish word 'flaquita' comes from combining the adjective 'flaco' (meaning 'thin' or 'weak') with the feminine diminutive suffix '-ita'. The base word 'flaco' itself derives from the Latin word 'flaccus', which meant 'flabby' or 'weak'. When the feminine diminutive '-ita' is added to 'flaco', it creates an affectionate or diminutive form meaning 'little thin one' (feminine).

This transformation from Latin to Spanish shows how the double 'cc' in 'flaccus' simplified to 'c' in Spanish 'flaco', while maintaining a similar meaning related to thinness or weakness. The addition of '-ita' follows a common Spanish pattern of using diminutives to express smallness, endearment, or affection.

The simpler and more common Spanish word 'flaco/flaca' is directly related to 'flaquita'. While 'flaco' (masculine) or 'flaca' (feminine) simply means 'thin' or 'skinny', 'flaquita' adds an element of endearment or diminutiveness. You might hear 'flaca' as a casual nickname for a thin person, while 'flaquita' would be an even more affectionate version of this.

While there aren't many common English words directly derived from Latin 'flaccus', the English word 'flaccid' (meaning soft, limp, or weak) shares this Latin ancestor. You can see how both Spanish 'flaco/flaquita' and English 'flaccid' retained aspects of the original Latin meaning of weakness or limpness, though Spanish focused more on the 'thin' aspect while English preserved more of the 'soft/weak' sense.