lean

1 lean /ˈliːn/ verb
leans; leaned or British leant /ˈlɛnt/ ; leaning
1 lean
/ˈliːn/
verb
leans; leaned or British leant /ˈlɛnt/ ; leaning
Britannica Dictionary definition of LEAN
1 
a  [no object] : to bend or move from a straight position
b  [+ object] : to cause (something) to bend or move from a straight position
2 
a  [no object] : to rest on or against something or someone for support
b  [+ object] : to cause (something) to rest on or against something
3 
a  — used to describe what someone wants to do, tends to do, or is likely to do
— often + toward
b  — used to say that someone supports one group or set of beliefs more than another — often + toward
c  — used to say that something is more like one thing than another — often + toward

lean on

[phrasal verb]
1 
lean on (someone or something) : to depend on (someone or something) for support
2 
lean on (someone) informal : to force or try to force (someone) to do something especially by making threats : to put pressure on (someone)

lean over backward

— see 1backward
2 lean /liːn/ adjective
leaner; leanest
2 lean
/liːn/
adjective
leaner; leanest
Britannica Dictionary definition of LEAN
[also more lean; most lean]
1 
: not having much fat on the body : physically thin, strong, and healthy
2 
: containing little or no fat
3 
: not having or producing much money, food, etc.
4 
usually approving : not using a lot of something (such as words or money)
: not wasteful

— leanness

/ˈliːnnəs/ noun [noncount]
lean , thin , and skinny mean not having much fat on the body.
lean suggests a lack of unnecessary fat and may also suggest the muscular body of an athlete.
thin can describe a person whose lack of fat is unhealthy, but it also often describes a person who is considered attractive.
skinny describes a person who has an extremely thin appearance and who may not be healthy or eat enough food.