慕 is a bound morpheme (b.f.) that cannot stand alone—it always appears in compounds. Its core meaning is 'to admire' or 'hold in high regard', but it can also carry a nuance of envy (as in 羡慕 'to envy'). You'll encounter it in words like 仰慕 (to look up to/admire), 爱慕 (to adore), and 慕名 (driven by reputation). When you see 慕 in a compound, it typically contributes the sense of strong positive emotion toward someone or something.