The purpose of the present study was to determine what features associated with the macrolevel of lexical competence vary as a function of an increase in second language (L2) proficiency. The macrolevel of participants' word knowledge was described with respect to six variables that are commonly associated with three proposed macrolevel dimensions, namely quantity, quality, and metacognitive awareness. Sixty-four participants (native speakers of English, L2 advanced learners, and intermediate learners of English) self-rated their familiarity with 73 lexical items and were asked to generate word associations to the words they identified in a verifiable way as known. The data analyses showed that some measures, such as vocabulary size, word frequency effects, number of associations, and within-group consistency of participants' associative domain, are more sensitive to L2 learners' increasing proficiency than others (e.g., nativelike commonality of associations). We thus conclude that some aspects, such as quality and quantity of L2 lexical competence, develop as the proficiency of the L2 learners increases, whereas others, such as learners' metacognitive awareness, are not proficiency dependent. We also suggest that the measures that were identified as sensitive to capturing the overall state of L2 learners' vocabularies would also be reliable indexes of learners' proficiency development.